                    GNU Free Documentation License

                     Version 1.3, 3 November 2008

Copyright ¸ 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
<https://fsf.org/>

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.

The "publisher" means any person or entity that distributes copies of the
Document to the public.

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 front-matter 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 under this License. Any attempt otherwise to copy, modify,
sublicense, or distribute it is void, and will automatically terminate your
rights under this License.

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, receipt of a
copy of some or all of the same material does not give you any rights to use
it.

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 https://www.gnu.org/licenses/.

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

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide
Web server that publishes copyrightable works and also provides prominent
facilities for anybody to edit those works. A public wiki that anybody can
edit is an example of such a server. A "Massive Multiauthor Collaboration" (or
"MMC") contained in the site means any set of copyrightable works thus
published on the MMC site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 license
published by Creative Commons Corporation, a not-for-profit corporation with a
principal place of business in San Francisco, California, as well as future
copyleft versions of that license published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or in part,
as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this License, and
if all works that were first published under this License somewhere other than
this MMC, and subsequently incorporated in whole or in part into the MMC, (1)
had no cover texts or invariant sections, and (2) were thus incorporated prior
to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site under
CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC
is eligible for relicensing.

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 1.3 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.

