GNU Free Documentation License, v1.2
GNU Free Documentation License, Version 1.2, November 2002
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The purpose of this License is to make a manual, textbook, or other functional and useful document "free" in the
sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it,
either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to
get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in
the same sense. It complements the GNU General Public License, which is a copyleft license designed for free
We have designed this License in order to use it for manuals for free software, because free software needs free
documentation: a free program should come with manuals providing the same freedoms that the software does. But
this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or
whether it is published as a printed book. We recommend this License principally for works whose purpose is
instruction or reference.
APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright
holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free
license, unlimited in duration, to use that work under the conditions stated herein. The "Document", below, refers to
any such manual or work. Any member of the public is a licensee, and is addressed as "you". You accept the license
if you copy, modify or distribute the work in a way requiring permission under copyright law.
A "Modified Version" of the Document means any work containing the Document or a portion of it, either copied
verbatim, or with modifications and/or translated into another language.
A "Secondary Section" is a named appendix or a front-matter section of the Document that deals exclusively with the
relationship of the publishers or authors of the Document to the Document's overall subject (or to related matters) and
contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of
mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical
connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position
The "Invariant Sections" are certain Secondary Sections whose titles are designated, as being those of Invariant