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GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

Copyright © 2007 Free Software Foundation, Inc. <http://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license 
document, but changing it is not allowed.

Preamble

The GNU General Public License is a free, copyleft license for software and 
other kinds of works.

The licenses for most software and other practical works are designed to take 
away your freedom to share and change the works. By contrast, the GNU General 
Public License is intended to guarantee your freedom to share and change all 
versions of a program--to make sure it remains free software for all its users. 
We, the Free Software Foundation, use the GNU General Public License for most 
of our software; it applies also to any other work released this way by its 
authors. You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our 
General Public Licenses are designed to make sure that you have the freedom to 
distribute copies of free software (and charge for them if you wish), that you 
receive source code or can get it if you want it, that you can change the 
software or use pieces of it in new free programs, and that you know you can do 
these things.

To protect your rights, we need to prevent others from denying you these rights 
or asking you to surrender the rights. Therefore, you have certain 
responsibilities if you distribute copies of the software, or if you modify it: 
responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis or for 
a fee, you must pass on to the recipients the same freedoms that you received. 
You must make sure that they, too, receive or can get the source code. And you 
must show them these terms so they know their rights.

Developers that use the GNU GPL protect your rights with two steps: (1) assert 
copyright on the software, and (2) offer you this License giving you legal 
permission to copy, distribute and/or modify it.

For the developers' and authors' protection, the GPL clearly explains that 
there is no warranty for this free software. For both users' and authors' sake, 
the GPL requires that modified versions be marked as changed, so that their 
problems will not be attributed erroneously to authors of previous versions.

Some devices are designed to deny users access to install or run modified 
versions of the software inside them, although the manufacturer can do so. This 
is fundamentally incompatible with the aim of protecting users' freedom to 
change the software. The systematic pattern of such abuse occurs in the area of 
products for individuals to use, which is precisely where it is most 
unacceptable. Therefore, we have designed this version of the GPL to prohibit 
the practice for those products. If such problems arise substantially in other 
domains, we stand ready to extend this provision to those domains in future 
versions of the GPL, as needed to protect the freedom of users.

Finally, every program is threatened constantly by software patents. States 
should not allow patents to restrict development and use of software on 
general-purpose computers, but in those that do, we wish to avoid the special 
danger that patents applied to a free program could make it effectively 
proprietary. To prevent this, the GPL assures that patents cannot be used to 
render the program non-free.

The precise terms and conditions for copying, distribution and modification 
follow.

TERMS AND CONDITIONS

0. Definitions.

“This License” refers to version 3 of the GNU General Public License.

“Copyright” also means copyright-like laws that apply to other kinds of 
works, such as semiconductor masks.

“The Program” refers to any copyrightable work licensed under this License. 
Each licensee is addressed as “you”. “Licensees” and “recipients” 
may be individuals or organizations.

To “modify” a work means to copy from or adapt all or part of the work in a 
fashion requiring copyright permission, other than the making of an exact copy. 
The resulting work is called a “modified version” of the earlier work or a 
work “based on” the earlier work.

A “covered work” means either the unmodified Program or a work based on the 
Program.

To “propagate” a work means to do anything with it that, without 
permission, would make you directly or secondarily liable for infringement 
under applicable copyright law, except executing it on a computer or modifying 
a private copy. Propagation includes copying, distribution (with or without 
modification), making available to the public, and in some countries other 
activities as well.

To “convey” a work means any kind of propagation that enables other parties 
to make or receive copies. Mere interaction with a user through a computer 
network, with no transfer of a copy, is not conveying.

An interactive user interface displays “Appropriate Legal Notices” to the 
extent that it includes a convenient and prominently visible feature that (1) 
displays an appropriate copyright notice, and (2) tells the user that there is 
no warranty for the work (except to the extent that warranties are provided), 
that licensees may convey the work under this License, and how to view a copy 
of this License. If the interface presents a list of user commands or options, 
such as a menu, a prominent item in the list meets this criterion.

1. Source Code.
The “source code” for a work means the preferred form of the work for 
making modifications to it. “Object code” means any non-source form of a 
work.

A “Standard Interface” means an interface that either is an official 
standard defined by a recognized standards body, or, in the case of interfaces 
specified for a particular programming language, one that is widely used among 
developers working in that language.

The “System Libraries” of an executable work include anything, other than 
the work as a whole, that (a) is included in the normal form of packaging a 
Major Component, but which is not part of that Major Component, and (b) serves 
only to enable use of the work with that Major Component, or to implement a 
Standard Interface for which an implementation is available to the public in 
source code form. A “Major Component”, in this context, means a major 
essential component (kernel, window system, and so on) of the specific 
operating system (if any) on which the executable work runs, or a compiler used 
to produce the work, or an object code interpreter used to run it.

The “Corresponding Source” for a work in object code form means all the 
source code needed to generate, install, and (for an executable work) run the 
object code and to modify the work, including scripts to control those 
activities. However, it does not include the work's System Libraries, or 
general-purpose tools or generally available free programs which are used 
unmodified in performing those activities but which are not part of the work. 
For example, Corresponding Source includes interface definition files 
associated with source files for the work, and the source code for shared 
libraries and dynamically linked subprograms that the work is specifically 
designed to require, such as by intimate data communication or control flow 
between those subprograms and other parts of the work.

The Corresponding Source need not include anything that users can regenerate 
automatically from other parts of the Corresponding Source.

The Corresponding Source for a work in source code form is that same work.

2. Basic Permissions.
All rights granted under this License are granted for the term of copyright on 
the Program, and are irrevocable provided the stated conditions are met. This 
License explicitly affirms your unlimited permission to run the unmodified 
Program. The output from running a covered work is covered by this License only 
if the output, given its content, constitutes a covered work. This License 
acknowledges your rights of fair use or other equivalent, as provided by 
copyright law.

You may make, run and propagate covered works that you do not convey, without 
conditions so long as your license otherwise remains in force. You may convey 
covered works to others for the sole purpose of having them make modifications 
exclusively for you, or provide you with facilities for running those works, 
provided that you comply with the terms of this License in conveying all 
material for which you do not control copyright. Those thus making or running 
the covered works for you must do so exclusively on your behalf, under your 
direction and control, on terms that prohibit them from making any copies of 
your copyrighted material outside their relationship with you.

Conveying under any other circumstances is permitted solely under the 
conditions stated below. Sublicensing is not allowed; section 10 makes it 
unnecessary.

3. Protecting Users' Legal Rights From Anti-Circumvention Law.
No covered work shall be deemed part of an effective technological measure 
under any applicable law fulfilling obligations under article 11 of the WIPO 
copyright treaty adopted on 20 December 1996, or similar laws prohibiting or 
restricting circumvention of such measures.

When you convey a covered work, you waive any legal power to forbid 
circumvention of technological measures to the extent such circumvention is 
effected by exercising rights under this License with respect to the covered 
work, and you disclaim any intention to limit operation or modification of the 
work as a means of enforcing, against the work's users, your or third parties' 
legal rights to forbid circumvention of technological measures.

4. Conveying Verbatim Copies.
You may convey verbatim copies of the Program's source code as you receive it, 
in any medium, provided that you conspicuously and appropriately publish on 
each copy an appropriate copyright notice; keep intact all notices stating that 
this License and any non-permissive terms added in accord with section 7 apply 
to the code; keep intact all notices of the absence of any warranty; and give 
all recipients a copy of this License along with the Program.

You may charge any price or no price for each copy that you convey, and you may 
offer support or warranty protection for a fee.

5. Conveying Modified Source Versions.
You may convey a work based on the Program, or the modifications to produce it 
from the Program, in the form of source code under the terms of section 4, 
provided that you also meet all of these conditions:

     a) The work must carry prominent notices stating that you modified it, and 
giving a relevant date.

     b) The work must carry prominent notices stating that it is released under 
this License and any conditions added under section 7. This requirement 
modifies the requirement in section 4 to “keep intact all notices”.

     c) You must license the entire work, as a whole, under this License to 
anyone who comes into possession of a copy. This License will therefore apply, 
along with any applicable section 7 additional terms, to the whole of the work, 
and all its parts, regardless of how they are packaged. This License gives no 
permission to license the work in any other way, but it does not invalidate 
such permission if you have separately received it.

     d) If the work has interactive user interfaces, each must display 
Appropriate Legal Notices; however, if the Program has interactive interfaces 
that do not display Appropriate Legal Notices, your work need not make them do 
so.

A compilation of a covered work with other separate and independent works, 
which are not by their nature extensions of the covered work, and which are not 
combined with it such as to form a larger program, in or on a volume of a 
storage or distribution medium, is called an “aggregate” if the compilation 
and its resulting copyright are not used to limit the access or legal rights of 
the compilation's users beyond what the individual works permit. Inclusion of a 
covered work in an aggregate does not cause this License to apply to the other 
parts of the aggregate.

6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms of sections 4 
and 5, provided that you also convey the machine-readable Corresponding Source 
under the terms of this License, in one of these ways:

     a) Convey the object code in, or embodied in, a physical product 
(including a physical distribution medium), accompanied by the Corresponding 
Source fixed on a durable physical medium customarily used for software 
interchange.

     b) Convey the object code in, or embodied in, a physical product 
(including a physical distribution medium), accompanied by a written offer, 
valid for at least three years and valid for as long as you offer spare parts 
or customer support for that product model, to give anyone who possesses the 
object code either (1) a copy of the Corresponding Source for all the software 
in the product that is covered by this License, on a durable physical medium 
customarily used for software interchange, for a price no more than your 
reasonable cost of physically performing this conveying of source, or (2) 
access to copy the Corresponding Source from a network server at no charge.

     c) Convey individual copies of the object code with a copy of the written 
offer to provide the Corresponding Source. This alternative is allowed only 
occasionally and noncommercially, and only if you received the object code with 
such an offer, in accord with subsection 6b.

     d) Convey the object code by offering access from a designated place 
(gratis or for a charge), and offer equivalent access to the Corresponding 
Source in the same way through the same place at no further charge. You need 
not require recipients to copy the Corresponding Source along with the object 
code. If the place to copy the object code is a network server, the 
Corresponding Source may be on a different server (operated by you or a third 
party) that supports equivalent copying facilities, provided you maintain clear 
directions next to the object code saying where to find the Corresponding 
Source. Regardless of what server hosts the Corresponding Source, you remain 
obligated to ensure that it is available for as long as needed to satisfy these 
requirements.

     e) Convey the object code using peer-to-peer transmission, provided you 
inform other peers where the object code and Corresponding Source of the work 
are being offered to the general public at no charge under subsection 6d.

A separable portion of the object code, whose source code is excluded from the 
Corresponding Source as a System Library, need not be included in conveying the 
object code work.

A “User Product” is either (1) a “consumer product”, which means any 
tangible personal property which is normally used for personal, family, or 
household purposes, or (2) anything designed or sold for incorporation into a 
dwelling. In determining whether a product is a consumer product, doubtful 
cases shall be resolved in favor of coverage. For a particular product received 
by a particular user, “normally used” refers to a typical or common use of 
that class of product, regardless of the status of the particular user or of 
the way in which the particular user actually uses, or expects or is expected 
to use, the product. A product is a consumer product regardless of whether the 
product has substantial commercial, industrial or non-consumer uses, unless 
such uses represent the only significant mode of use of the product.

“Installation Information” for a User Product means any methods, 
procedures, authorization keys, or other information required to install and 
execute modified versions of a covered work in that User Product from a 
modified version of its Corresponding Source. The information must suffice to 
ensure that the continued functioning of the modified object code is in no case 
prevented or interfered with solely because modification has been made.

If you convey an object code work under this section in, or with, or 
specifically for use in, a User Product, and the conveying occurs as part of a 
transaction in which the right of possession and use of the User Product is 
transferred to the recipient in perpetuity or for a fixed term (regardless of 
how the transaction is characterized), the Corresponding Source conveyed under 
this section must be accompanied by the Installation Information. But this 
requirement does not apply if neither you nor any third party retains the 
ability to install modified object code on the User Product (for example, the 
work has been installed in ROM).

The requirement to provide Installation Information does not include a 
requirement to continue to provide support service, warranty, or updates for a 
work that has been modified or installed by the recipient, or for the User 
Product in which it has been modified or installed. Access to a network may be 
denied when the modification itself materially and adversely affects the 
operation of the network or violates the rules and protocols for communication 
across the network.

Corresponding Source conveyed, and Installation Information provided, in accord 
with this section must be in a format that is publicly documented (and with an 
implementation available to the public in source code form), and must require 
no special password or key for unpacking, reading or copying.

7. Additional Terms.
“Additional permissions” are terms that supplement the terms of this 
License by making exceptions from one or more of its conditions. Additional 
permissions that are applicable to the entire Program shall be treated as 
though they were included in this License, to the extent that they are valid 
under applicable law. If additional permissions apply only to part of the 
Program, that part may be used separately under those permissions, but the 
entire Program remains governed by this License without regard to the 
additional permissions.

When you convey a copy of a covered work, you may at your option remove any 
additional permissions from that copy, or from any part of it. (Additional 
permissions may be written to require their own removal in certain cases when 
you modify the work.) You may place additional permissions on material, added 
by you to a covered work, for which you have or can give appropriate copyright 
permission.

Notwithstanding any other provision of this License, for material you add to a 
covered work, you may (if authorized by the copyright holders of that material) 
supplement the terms of this License with terms:

     a) Disclaiming warranty or limiting liability differently from the terms 
of sections 15 and 16 of this License; or

     b) Requiring preservation of specified reasonable legal notices or author 
attributions in that material or in the Appropriate Legal Notices displayed by 
works containing it; or

     c) Prohibiting misrepresentation of the origin of that material, or 
requiring that modified versions of such material be marked in reasonable ways 
as different from the original version; or

     d) Limiting the use for publicity purposes of names of licensors or 
authors of the material; or

     e) Declining to grant rights under trademark law for use of some trade 
names, trademarks, or service marks; or

     f) Requiring indemnification of licensors and authors of that material by 
anyone who conveys the material (or modified versions of it) with contractual 
assumptions of liability to the recipient, for any liability that these 
contractual assumptions directly impose on those licensors and authors.

All other non-permissive additional terms are considered “further 
restrictions” within the meaning of section 10. If the Program as you 
received it, or any part of it, contains a notice stating that it is governed 
by this License along with a term that is a further restriction, you may remove 
that term. If a license document contains a further restriction but permits 
relicensing or conveying under this License, you may add to a covered work 
material governed by the terms of that license document, provided that the 
further restriction does not survive such relicensing or conveying.

If you add terms to a covered work in accord with this section, you must place, 
in the relevant source files, a statement of the additional terms that apply to 
those files, or a notice indicating where to find the applicable terms.

Additional terms, permissive or non-permissive, may be stated in the form of a 
separately written license, or stated as exceptions; the above requirements 
apply either way.

8. Termination.
You may not propagate or modify a covered work except as expressly provided 
under this License. Any attempt otherwise to propagate or modify it is void, 
and will automatically terminate your rights under this License (including any 
patent licenses granted under the third paragraph of section 11).

However, if you cease all violation of this License, then your license from a 
particular copyright holder is reinstated (a) provisionally, unless and until 
the copyright holder explicitly and finally terminates your license, and (b) 
permanently, if the copyright holder fails to notify you of the violation by 
some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated 
permanently if the copyright holder notifies you of the violation by some 
reasonable means, this is the first time you have received notice of violation 
of this License (for any work) from that copyright holder, and you cure the 
violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses 
of parties who have received copies or rights from you under this License. If 
your rights have been terminated and not permanently reinstated, you do not 
qualify to receive new licenses for the same material under section 10.

9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy 
of the Program. Ancillary propagation of a covered work occurring solely as a 
consequence of using peer-to-peer transmission to receive a copy likewise does 
not require acceptance. However, nothing other than this License grants you 
permission to propagate or modify any covered work. These actions infringe 
copyright if you do not accept this License. Therefore, by modifying or 
propagating a covered work, you indicate your acceptance of this License to do 
so.

10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically receives a 
license from the original licensors, to run, modify and propagate that work, 
subject to this License. You are not responsible for enforcing compliance by 
third parties with this License.

An “entity transaction” is a transaction transferring control of an 
organization, or substantially all assets of one, or subdividing an 
organization, or merging organizations. If propagation of a covered work 
results from an entity transaction, each party to that transaction who receives 
a copy of the work also receives whatever licenses to the work the party's 
predecessor in interest had or could give under the previous paragraph, plus a 
right to possession of the Corresponding Source of the work from the 
predecessor in interest, if the predecessor has it or can get it with 
reasonable efforts.

You may not impose any further restrictions on the exercise of the rights 
granted or affirmed under this License. For example, you may not impose a 
license fee, royalty, or other charge for exercise of rights granted under this 
License, and you may not initiate litigation (including a cross-claim or 
counterclaim in a lawsuit) alleging that any patent claim is infringed by 
making, using, selling, offering for sale, or importing the Program or any 
portion of it.

11. Patents.
A “contributor” is a copyright holder who authorizes use under this License 
of the Program or a work on which the Program is based. The work thus licensed 
is called the contributor's “contributor version”.

A contributor's “essential patent claims” are all patent claims owned or 
controlled by the contributor, whether already acquired or hereafter acquired, 
that would be infringed by some manner, permitted by this License, of making, 
using, or selling its contributor version, but do not include claims that would 
be infringed only as a consequence of further modification of the contributor 
version. For purposes of this definition, “control” includes the right to 
grant patent sublicenses in a manner consistent with the requirements of this 
License.

Each contributor grants you a non-exclusive, worldwide, royalty-free patent 
license under the contributor's essential patent claims, to make, use, sell, 
offer for sale, import and otherwise run, modify and propagate the contents of 
its contributor version.

In the following three paragraphs, a “patent license” is any express 
agreement or commitment, however denominated, not to enforce a patent (such as 
an express permission to practice a patent or covenant not to sue for patent 
infringement). To “grant” such a patent license to a party means to make 
such an agreement or commitment not to enforce a patent against the party.

If you convey a covered work, knowingly relying on a patent license, and the 
Corresponding Source of the work is not available for anyone to copy, free of 
charge and under the terms of this License, through a publicly available 
network server or other readily accessible means, then you must either (1) 
cause the Corresponding Source to be so available, or (2) arrange to deprive 
yourself of the benefit of the patent license for this particular work, or (3) 
arrange, in a manner consistent with the requirements of this License, to 
extend the patent license to downstream recipients. “Knowingly relying” 
means you have actual knowledge that, but for the patent license, your 
conveying the covered work in a country, or your recipient's use of the covered 
work in a country, would infringe one or more identifiable patents in that 
country that you have reason to believe are valid.

If, pursuant to or in connection with a single transaction or arrangement, you 
convey, or propagate by procuring conveyance of, a covered work, and grant a 
patent license to some of the parties receiving the covered work authorizing 
them to use, propagate, modify or convey a specific copy of the covered work, 
then the patent license you grant is automatically extended to all recipients 
of the covered work and works based on it.

A patent license is “discriminatory” if it does not include within the 
scope of its coverage, prohibits the exercise of, or is conditioned on the 
non-exercise of one or more of the rights that are specifically granted under 
this License. You may not convey a covered work if you are a party to an 
arrangement with a third party that is in the business of distributing 
software, under which you make payment to the third party based on the extent 
of your activity of conveying the work, and under which the third party grants, 
to any of the parties who would receive the covered work from you, a 
discriminatory patent license (a) in connection with copies of the covered work 
conveyed by you (or copies made from those copies), or (b) primarily for and in 
connection with specific products or compilations that contain the covered 
work, unless you entered into that arrangement, or that patent license was 
granted, prior to 28 March 2007.

Nothing in this License shall be construed as excluding or limiting any implied 
license or other defenses to infringement that may otherwise be available to 
you under applicable patent law.

12. No Surrender of Others' Freedom.
If conditions are imposed on you (whether by court order, agreement or 
otherwise) that contradict the conditions of this License, they do not excuse 
you from the conditions of this License. If you cannot convey a covered work so 
as to satisfy simultaneously your obligations under this License and any other 
pertinent obligations, then as a consequence you may not convey it at all. For 
example, if you agree to terms that obligate you to collect a royalty for 
further conveying from those to whom you convey the Program, the only way you 
could satisfy both those terms and this License would be to refrain entirely 
from conveying the Program.

13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have permission to 
link or combine any covered work with a work licensed under version 3 of the 
GNU Affero General Public License into a single combined work, and to convey 
the resulting work. The terms of this License will continue to apply to the 
part which is the covered work, but the special requirements of the GNU Affero 
General Public License, section 13, concerning interaction through a network 
will apply to the combination as such.

14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new versions of the GNU 
General Public License from time to time. Such new versions will be similar in 
spirit to the present version, but may differ in detail to address new problems 
or concerns.

Each version is given a distinguishing version number. If the Program specifies 
that a certain numbered version of the GNU General Public License “or any 
later version” applies to it, you have the option of following the terms and 
conditions either of that numbered version or of any later version published by 
the Free Software Foundation. If the Program does not specify a version number 
of the GNU General Public License, you may choose any version ever published by 
the Free Software Foundation.

If the Program specifies that a proxy can decide which future versions of the 
GNU General Public License can be used, that proxy's public statement of 
acceptance of a version permanently authorizes you to choose that version for 
the Program.

Later license versions may give you additional or different permissions. 
However, no additional obligations are imposed on any author or copyright 
holder as a result of your choosing to follow a later version.

15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE 
LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER 
PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER 
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE 
QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE 
DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY 
COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS 
PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, 
INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE 
THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED 
INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE 
PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY 
HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot 
be given local legal effect according to their terms, reviewing courts shall 
apply local law that most closely approximates an absolute waiver of all civil 
liability in connection with the Program, unless a warranty or assumption of 
liability accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible 
use to the public, the best way to achieve this is to make it free software 
which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach 
them to the start of each source file to most effectively state the exclusion 
of warranty; and each file should have at least the “copyright” line and a 
pointer to where the full notice is found.

     <one line to give the program's name and a brief idea of what it does.>
     Copyright (C) <year>  <name of author>

     This program is free software: you can redistribute it and/or modify it 
under the terms of the GNU General Public License as published by the Free 
Software Foundation, either version 3 of the License, or (at your option) any 
later version.

     This program is distributed in the hope that it will be useful, but 
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more 
details.

     You should have received a copy of the GNU General Public License along 
with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice like 
this when it starts in an interactive mode:

     <program>  Copyright (C) <year>  <name of author>
     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it under 
certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate 
parts of the General Public License. Of course, your program's commands might 
be different; for a GUI interface, you would use an “about box”.

You should also get your employer (if you work as a programmer) or school, if 
any, to sign a “copyright disclaimer” for the program, if necessary. For 
more information on this, and how to apply and follow the GNU GPL, see 
<http://www.gnu.org/licenses/>.

The GNU General Public License does not permit incorporating your program into 
proprietary programs. If your program is a subroutine library, you may consider 
it more useful to permit linking proprietary applications with the library. If 
this is what you want to do, use the GNU Lesser General Public License instead 
of this License. But first, please read 
<http://www.gnu.org/philosophy/why-not-lgpl.html>.