GNU Free Documentation License Version 1.2,
November 2002 Copyright (C) 2000,2001,2002
Free Software Foundation, Inc. 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute
verbatim copies of this license document, but
changing it is not allowed.
0. PREAMBLE
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 software. 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.
1. 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 regarding them. The "Invariant Sections" are
certain Secondary Sections whose titles are designated, as being
those of Invariant Sections, in the notice that says that the
Document is released under this License. If a section does not fit
the above definition of Secondary then it is not allowed to be
designated as Invariant. The Document may contain zero
Invariant Sections. If the Document does not identify any Invariant
Sections then there are none. The "Cover Texts" are certain short
passages of text that are listed, as Front-Cover Texts or Back-
Cover Texts, in the notice that says that the Document is
released under this License. A Front-Cover Text may be at most
5 words, and a Back-Cover Text may be at most 25 words. A
"Transparent" copy of the Document means a machine-readable
copy, represented in a format whose specification is available to
the general public, that is suitable for revising the document
straightforwardly with generic text editors or (for images
composed of pixels) generic paint programs or (for drawings)
some widely available drawing editor, and that is suitable for input
to text formatters or for automatic translation to a variety of
formats suitable for input to text formatters. A copy made in an
otherwise Transparent file format whose markup, or absence of
markup, has been arranged to thwart or discourage subsequent
modification by readers is not Transparent. An image format is
not Transparent if used for any substantial amount of text. A copy
that is not "Transparent" is called "Opaque". Examples of suitable
formats for Transparent copies include plain ASCII without
markup, Texinfo input format, LaTeX input format, SGML or XML
using a publicly available DTD, and standard-conforming simple
HTML, PostScript or PDF designed for human modification.
Examples of transparent image formats include PNG, XCF and
JPG. Opaque formats include proprietary formats that can be
read and edited only by proprietary word processors, SGML or
XML for which the DTD and/or processing tools are not generally
available, and the machine-generated HTML, PostScript or PDF
produced by some word processors for output purposes only. The
"Title Page" means, for a printed book, the title page itself, plus
such following pages as are needed to hold, legibly, the material
this License requires to appear in the title page. For works in
formats which do not have any title page as such, "Title Page"
means the text near the most prominent appearance of the work's
title, preceding the beginning of the body of the text. A section
"Entitled XYZ" means a named subunit of the Document whose
title either is precisely XYZ or contains XYZ in parentheses
following text that translates XYZ in another language. (Here XYZ
stands for a specific section name mentioned below, such as
"Acknowledgements", "Dedications", "Endorsements", or
"History".) To "Preserve the Title" of such a section when you
modify the Document means that it remains a section "Entitled
XYZ" according to this definition. The Document may include
Warranty Disclaimers next to the notice which states that this
License applies to the Document. These Warranty Disclaimers
are considered to be included by reference in this License, but
only as regards disclaiming warranties: any other implication that
these Warranty Disclaimers may have is void and has no effect
on the meaning of this License.
2. VERBATIM COPYING
You may copy and distribute the Document in any medium,
either commercially or noncommercially, provided that this
License, the copyright notices, and the license notice saying this
License applies to the Document are reproduced in all copies,
and that you add no other conditions whatsoever to those of this
License. You may not use technical measures to obstruct or
control the reading or further copying of the copies you make or
distribute. However, you may accept compensation in exchange
for copies. If you distribute a large enough number of copies you
must also follow the conditions in section 3. You may also lend
copies, under the same conditions stated above, and you may
publicly display copies.
3. COPYING IN QUANTITY
If you publish printed copies (or copies in media that commonly
have printed covers) of the Document, numbering more than 100,
and the Document's license notice requires Cover Texts, you
must enclose the copies in covers that carry, clearly and legibly,
all these Cover Texts: Front-Cover Texts on the front cover, and
Back-Cover Texts on the back cover. Both covers must also
clearly and legibly identify you as the publisher of these copies.
The front cover must present the full title with all words of the title
equally prominent and visible. You may add other material on the
covers in addition. Copying with changes limited to the covers, as
long as they preserve the title of the Document and satisfy these
conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
reasonably) on the actual cover, and continue the rest onto
adjacent pages. If you publish or distribute Opaque copies of the
Document numbering more than 100, you must either include a
machine-readable Transparent copy along with each Opaque
copy, or state in or with each Opaque copy a computer-network
location from which the general network-using public has access
to download using public-standard network protocols a complete
Transparent copy of the Document, free of added material. If you
use the latter option, you must take reasonably prudent steps,
when you begin distribution of Opaque copies in quantity, to
ensure that this Transparent copy will remain thus accessible at
the stated location until at least one year after the last time you
distribute an Opaque copy (directly or through your agents or
retailers) of that edition to the public. It is requested, but not
required, that you contact the authors of the Document well
before redistributing any large number of copies, to give them a
chance to provide you with an updated version of the Document.
4. MODIFICATIONS
You may copy and distribute a Modified Version of the Document
under the conditions of sections 2 and 3 above, provided that you
release the Modified Version under precisely this License, with
the Modified Version filling the role of the Document, thus
licensing distribution and modification of the Modified Version to
whoever possesses a copy of it. In addition, you must do these
things in the Modified Version: A. Use in the Title Page (and on
the covers, if any) a title distinct from that of the Document, and
from those of previous versions (which should, if there were any,
be listed in the History section of the Document). You may use
the same title as a previous version if the original publisher of that
version gives permission. B. List on the Title Page, as authors,
one or more persons or entities responsible for authorship of the
modifications in the Modified Version, together with at least five of
the principal authors of the Document (all of its principal authors,
if it has fewer than five), unless they release you from this
requirement. C. State on the Title page the name of the publisher
of the Modified Version, as the publisher. D. Preserve all the
copyright notices of the Document. E. Add an appropriate
copyright notice for your modifications adjacent to the other
copyright notices. F. Include, immediately after the copyright
notices, a license notice giving the public permission to use the
Modified Version under the terms of this License, in the form
shown in the Addendum below. G. Preserve in that license notice
the full lists of Invariant Sections and required Cover Texts given
in the Document's license notice. H. Include an unaltered copy of
this License. I. Preserve the section Entitled "History", Preserve
its Title, and add to it an item stating at least the title, year, new
authors, and publisher of the Modified Version as given on the
Title Page. If there is no section Entitled "History" in the
Document, create one stating the title, year, authors, and
publisher of the Document as given on its Title Page, then add an
item describing the Modified Version as stated in the previous
sentence. J. Preserve the network location, if any, given in the
Document for public access to a Transparent copy of the
Document, and likewise the network locations given in the
Document for previous versions it was based on. These may be
placed in the "History" section. You may omit a network location
for a work that was published at least four years before the
Document itself, or if the original publisher of the version it refers
to gives permission. K. For any section Entitled
"Acknowledgements" or "Dedications", Preserve the Title of the
section, and preserve in the section all the substance and tone of
each of the contributor acknowledgements and/or dedications
given therein. L. Preserve all the Invariant Sections of the
Document, unaltered in their text and in their titles. Section
numbers or the equivalent are not considered part of the section
titles. M. Delete any section Entitled "Endorsements". Such a
section may not be included in the Modified Version. N. Do not
retitle any existing section to be Entitled "Endorsements" or to
conflict in title with any Invariant Section. O. Preserve any
Warranty Disclaimers. If the Modified Version includes new frontmatter
sections or appendices that qualify as Secondary Sections
and contain no material copied from the Document, you may at
your option designate some or all of these sections as invariant.
To do this, add their titles to the list of Invariant Sections in the
Modified Version's license notice. These titles must be distinct
from any other section titles. You may add a section Entitled
"Endorsements", provided it contains nothing but endorsements
of your Modified Version by various parties--for example,
statements of peer review or that the text has been approved by
an organization as the authoritative definition of a standard. You
may add a passage of up to five words as a Front-Cover Text,
and a passage of up to 25 words as a Back-Cover Text, to the
end of the list of Cover Texts in the Modified Version. Only one
passage of Front-Cover Text and one of Back-Cover Text may be
added by (or through arrangements made by) any one entity. If
the Document already includes a cover text for the same cover,
previously added by you or by arrangement made by the same
entity you are acting on behalf of, you may not add another; but
you may replace the old one, on explicit permission from the
previous publisher that added the old one. The author(s) and
publisher(s) of the Document do not by this License give
permission to use their names for publicity for or to assert or imply
endorsement of any Modified Version.
5. COMBINING DOCUMENTS
You may combine the Document with other documents released
under this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination all
of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice, and that you preserve all their
Warranty Disclaimers. The combined work need only contain one
copy of this License, and multiple identical Invariant Sections may
be replaced with a single copy. If there are multiple Invariant
Sections with the same name but different contents, make the
title of each such section unique by adding at the end of it, in
parentheses, the name of the original author or publisher of that
section if known, or else a unique number. Make the same
adjustment to the section titles in the list of Invariant Sections in
the license notice of the combined work. In the combination, you
must combine any sections Entitled "History" in the various
original documents, forming one section Entitled "History";
likewise combine any sections Entitled "Acknowledgements", and
any sections Entitled "Dedications". You must delete all sections
Entitled "Endorsements".
6. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other
documents released under this License, and replace the
individual copies of this License in the various documents with a
single copy that is included in the collection, provided that you
follow the rules of this License for verbatim copying of each of the
documents in all other respects. You may extract a single
document from such a collection, and distribute it individually
under this License, provided you insert a copy of this License into
the extracted document, and follow this License in all other
respects regarding verbatim copying of that document.
7. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume
of a storage or distribution medium, is called an "aggregate" if the
copyright resulting from the compilation is not used to limit the
legal rights of the compilation's users beyond what the individual
works permit. When the Document is included in an aggregate,
this License does not apply to the other works in the aggregate
which are not themselves derivative works of the Document. If the
Cover Text requirement of section 3 is applicable to these copies
of the Document, then if the Document is less than one half of the
entire aggregate, the Document's Cover Texts may be placed on
covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic
form. Otherwise they must appear on printed covers that bracket
the whole aggregate.
8. TRANSLATION
Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section
4. Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also
include the original English version of this License and the
original versions of those notices and disclaimers. In case of a
disagreement between the translation and the original version of
this License or a notice or disclaimer, the original version will
prevail. If a section in the Document is Entitled
"Acknowledgements", "Dedications", or "History", the requirement
(section 4) to Preserve its Title (section 1) will typically require
changing the actual title.
9. TERMINATION
You may not copy, modify, sublicense, or distribute the
Document except as expressly provided for under this License.
Any other attempt to copy, modify, sublicense or distribute the
Document is void, and will automatically terminate your rights
under this License. However, parties who have received copies,
or rights, from you under this License will not have their licenses
terminated so long as such parties remain in full compliance.
10. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised
versions of the GNU Free Documentation 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. See http://www.gnu.org/copyleft/. Each version of the
License is given a distinguishing version number. If the Document
specifies that a particular numbered version of this License "or
any later version" applies to it, you have the option of following
the terms and conditions either of that specified version or of any
later version that has been published (not as a draft) by the Free
Software Foundation. If the Document does not specify a version
number of this License, you may choose any version ever
published (not as a draft) by the Free Software Foundation.
ADDENDUM: How to use this License for your documents To use
this License in a document you have written, include a copy of the
License in the document and put the following copyright and
license notices just after the title page: Copyright (c) YEAR YOUR
NAME. Permission is granted to copy, distribute and/or modify
this document under the terms of the GNU Free Documentation
License, Version 1.2 or any later version published by the Free
Software Foundation; with no Invariant Sections, no Front-Cover
Texts, and no Back-Cover Texts. A copy of the license is included
in the section entitled "GNU Free Documentation License". If you
have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts." line with this: with the Invariant
Sections being LIST THEIR TITLES, with the Front-Cover Texts
being LIST, and with the Back-Cover Texts being LIST. If you
have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation. If your document contains nontrivial examples of
program code, we recommend releasing these examples in
parallel under your choice of free software license, such as the
GNU General Public License, to permit their use in free software.