1 \chapter{GNU Free Documentation License}
5 Version 1.3, 3 November 2008
8 Copyright \copyright{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
12 <\url{http://fsf.org/}>
16 Everyone is permitted to copy and distribute verbatim copies
17 of this license document, but changing it is not allowed.
23 The purpose of this License is to make a manual, textbook, or other
24 functional and useful document ``free'' in the sense of freedom: to
25 assure everyone the effective freedom to copy and redistribute it,
26 with or without modifying it, either commercially or noncommercially.
27 Secondarily, this License preserves for the author and publisher a way
28 to get credit for their work, while not being considered responsible
29 for modifications made by others.
31 This License is a kind of ``copyleft'', which means that derivative
32 works of the document must themselves be free in the same sense. It
33 complements the GNU General Public License, which is a copyleft
34 license designed for free software.
36 We have designed this License in order to use it for manuals for free
37 software, because free software needs free documentation: a free
38 program should come with manuals providing the same freedoms that the
39 software does. But this License is not limited to software manuals;
40 it can be used for any textual work, regardless of subject matter or
41 whether it is published as a printed book. We recommend this License
42 principally for works whose purpose is instruction or reference.
45 \section{Applicability and Definitions}
47 This License applies to any manual or other work, in any medium, that
48 contains a notice placed by the copyright holder saying it can be
49 distributed under the terms of this License. Such a notice grants a
50 world-wide, royalty-free license, unlimited in duration, to use that
51 work under the conditions stated herein. The ``\textit{Document}'', below,
52 refers to any such manual or work. Any member of the public is a
53 licensee, and is addressed as ``\textit{you}''. You accept the license if you
54 copy, modify or distribute the work in a way requiring permission
57 A ``\textit{Modified Version}'' of the Document means any work containing the
58 Document or a portion of it, either copied verbatim, or with
59 modifications and/or translated into another language.
61 A ``\textit{Secondary Section}'' is a named appendix or a front-matter section of
62 the Document that deals exclusively with the relationship of the
63 publishers or authors of the Document to the Document's overall subject
64 (or to related matters) and contains nothing that could fall directly
65 within that overall subject. (Thus, if the Document is in part a
66 textbook of mathematics, a Secondary Section may not explain any
67 mathematics.) The relationship could be a matter of historical
68 connection with the subject or with related matters, or of legal,
69 commercial, philosophical, ethical or political position regarding
72 The ``\textit{Invariant Sections}'' are certain Secondary Sections whose titles
73 are designated, as being those of Invariant Sections, in the notice
74 that says that the Document is released under this License. If a
75 section does not fit the above definition of Secondary then it is not
76 allowed to be designated as Invariant. The Document may contain zero
77 Invariant Sections. If the Document does not identify any Invariant
78 Sections then there are none.
80 The ``\textit{Cover Texts}'' are certain short passages of text that are listed,
81 as Front-Cover Texts or Back-Cover Texts, in the notice that says that
82 the Document is released under this License. A Front-Cover Text may
83 be at most 5 words, and a Back-Cover Text may be at most 25 words.
85 A ``\textit{Transparent}'' copy of the Document means a machine-readable copy,
86 represented in a format whose specification is available to the
87 general public, that is suitable for revising the document
88 straightforwardly with generic text editors or (for images composed of
89 pixels) generic paint programs or (for drawings) some widely available
90 drawing editor, and that is suitable for input to text formatters or
91 for automatic translation to a variety of formats suitable for input
92 to text formatters. A copy made in an otherwise Transparent file
93 format whose markup, or absence of markup, has been arranged to thwart
94 or discourage subsequent modification by readers is not Transparent.
95 An image format is not Transparent if used for any substantial amount
96 of text. A copy that is not ``Transparent'' is called ``\textit{Opaque}''.
98 Examples of suitable formats for Transparent copies include plain
99 ASCII without markup, Texinfo input format, LaTeX input format, SGML
100 or XML using a publicly available DTD, and standard-conforming simple
101 HTML, PostScript or PDF designed for human modification. Examples of
102 transparent image formats include PNG, XCF and JPG. Opaque formats
103 include proprietary formats that can be read and edited only by
104 proprietary word processors, SGML or XML for which the DTD and/or
105 processing tools are not generally available, and the
106 machine-generated HTML, PostScript or PDF produced by some word
107 processors for output purposes only.
109 The ``\textit{Title Page}'' means, for a printed book, the title page itself,
110 plus such following pages as are needed to hold, legibly, the material
111 this License requires to appear in the title page. For works in
112 formats which do not have any title page as such, ``Title Page'' means
113 the text near the most prominent appearance of the work's title,
114 preceding the beginning of the body of the text.
116 The ``\textit{publisher}'' means any person or entity that distributes
117 copies of the Document to the public.
119 A section ``\textit{Entitled XYZ}'' means a named subunit of the Document whose
120 title either is precisely XYZ or contains XYZ in parentheses following
121 text that translates XYZ in another language. (Here XYZ stands for a
122 specific section name mentioned below, such as ``\textit{Acknowledgements}'',
123 ``\textit{Dedications}'', ``\textit{Endorsements}'', or ``\textit{History}''.)
124 To ``\textit{Preserve the Title}''
125 of such a section when you modify the Document means that it remains a
126 section ``Entitled XYZ'' according to this definition.
128 The Document may include Warranty Disclaimers next to the notice which
129 states that this License applies to the Document. These Warranty
130 Disclaimers are considered to be included by reference in this
131 License, but only as regards disclaiming warranties: any other
132 implication that these Warranty Disclaimers may have is void and has
133 no effect on the meaning of this License.
135 \section{Verbatim Copying}
137 You may copy and distribute the Document in any medium, either
138 commercially or noncommercially, provided that this License, the
139 copyright notices, and the license notice saying this License applies
140 to the Document are reproduced in all copies, and that you add no other
141 conditions whatsoever to those of this License. You may not use
142 technical measures to obstruct or control the reading or further
143 copying of the copies you make or distribute. However, you may accept
144 compensation in exchange for copies. If you distribute a large enough
145 number of copies you must also follow the conditions in section~3.
147 You may also lend copies, under the same conditions stated above, and
148 you may publicly display copies.
150 \section{Copying in Quantity}
152 If you publish printed copies (or copies in media that commonly have
153 printed covers) of the Document, numbering more than 100, and the
154 Document's license notice requires Cover Texts, you must enclose the
155 copies in covers that carry, clearly and legibly, all these Cover
156 Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
157 the back cover. Both covers must also clearly and legibly identify
158 you as the publisher of these copies. The front cover must present
159 the full title with all words of the title equally prominent and
160 visible. You may add other material on the covers in addition.
161 Copying with changes limited to the covers, as long as they preserve
162 the title of the Document and satisfy these conditions, can be treated
163 as verbatim copying in other respects.
165 If the required texts for either cover are too voluminous to fit
166 legibly, you should put the first ones listed (as many as fit
167 reasonably) on the actual cover, and continue the rest onto adjacent
170 If you publish or distribute Opaque copies of the Document numbering
171 more than 100, you must either include a machine-readable Transparent
172 copy along with each Opaque copy, or state in or with each Opaque copy
173 a computer-network location from which the general network-using
174 public has access to download using public-standard network protocols
175 a complete Transparent copy of the Document, free of added material.
176 If you use the latter option, you must take reasonably prudent steps,
177 when you begin distribution of Opaque copies in quantity, to ensure
178 that this Transparent copy will remain thus accessible at the stated
179 location until at least one year after the last time you distribute an
180 Opaque copy (directly or through your agents or retailers) of that
181 edition to the public.
183 It is requested, but not required, that you contact the authors of the
184 Document well before redistributing any large number of copies, to give
185 them a chance to provide you with an updated version of the Document.
188 \section{Modifications}
190 You may copy and distribute a Modified Version of the Document under
191 the conditions of sections 2 and 3 above, provided that you release
192 the Modified Version under precisely this License, with the Modified
193 Version filling the role of the Document, thus licensing distribution
194 and modification of the Modified Version to whoever possesses a copy
195 of it. In addition, you must do these things in the Modified Version:
199 Use in the Title Page (and on the covers, if any) a title distinct
200 from that of the Document, and from those of previous versions
201 (which should, if there were any, be listed in the History section
202 of the Document). You may use the same title as a previous version
203 if the original publisher of that version gives permission.
206 List on the Title Page, as authors, one or more persons or entities
207 responsible for authorship of the modifications in the Modified
208 Version, together with at least five of the principal authors of the
209 Document (all of its principal authors, if it has fewer than five),
210 unless they release you from this requirement.
213 State on the Title page the name of the publisher of the
214 Modified Version, as the publisher.
217 Preserve all the copyright notices of the Document.
220 Add an appropriate copyright notice for your modifications
221 adjacent to the other copyright notices.
224 Include, immediately after the copyright notices, a license notice
225 giving the public permission to use the Modified Version under the
226 terms of this License, in the form shown in the Addendum below.
229 Preserve in that license notice the full lists of Invariant Sections
230 and required Cover Texts given in the Document's license notice.
233 Include an unaltered copy of this License.
236 Preserve the section Entitled ``History'', Preserve its Title, and add
237 to it an item stating at least the title, year, new authors, and
238 publisher of the Modified Version as given on the Title Page. If
239 there is no section Entitled ``History'' in the Document, create one
240 stating the title, year, authors, and publisher of the Document as
241 given on its Title Page, then add an item describing the Modified
242 Version as stated in the previous sentence.
245 Preserve the network location, if any, given in the Document for
246 public access to a Transparent copy of the Document, and likewise
247 the network locations given in the Document for previous versions
248 it was based on. These may be placed in the ``History'' section.
249 You may omit a network location for a work that was published at
250 least four years before the Document itself, or if the original
251 publisher of the version it refers to gives permission.
254 For any section Entitled ``Acknowledgements'' or ``Dedications'',
255 Preserve the Title of the section, and preserve in the section all
256 the substance and tone of each of the contributor acknowledgements
257 and/or dedications given therein.
260 Preserve all the Invariant Sections of the Document,
261 unaltered in their text and in their titles. Section numbers
262 or the equivalent are not considered part of the section titles.
265 Delete any section Entitled ``Endorsements''. Such a section
266 may not be included in the Modified Version.
269 Do not retitle any existing section to be Entitled ``Endorsements''
270 or to conflict in title with any Invariant Section.
273 Preserve any Warranty Disclaimers.
276 If the Modified Version includes new front-matter sections or
277 appendices that qualify as Secondary Sections and contain no material
278 copied from the Document, you may at your option designate some or all
279 of these sections as invariant. To do this, add their titles to the
280 list of Invariant Sections in the Modified Version's license notice.
281 These titles must be distinct from any other section titles.
283 You may add a section Entitled ``Endorsements'', provided it contains
284 nothing but endorsements of your Modified Version by various
285 parties---for example, statements of peer review or that the text has
286 been approved by an organization as the authoritative definition of a
289 You may add a passage of up to five words as a Front-Cover Text, and a
290 passage of up to 25 words as a Back-Cover Text, to the end of the list
291 of Cover Texts in the Modified Version. Only one passage of
292 Front-Cover Text and one of Back-Cover Text may be added by (or
293 through arrangements made by) any one entity. If the Document already
294 includes a cover text for the same cover, previously added by you or
295 by arrangement made by the same entity you are acting on behalf of,
296 you may not add another; but you may replace the old one, on explicit
297 permission from the previous publisher that added the old one.
299 The author(s) and publisher(s) of the Document do not by this License
300 give permission to use their names for publicity for or to assert or
301 imply endorsement of any Modified Version.
304 \section{Combining Documents}
307 You may combine the Document with other documents released under this
308 License, under the terms defined in section~4 above for modified
309 versions, provided that you include in the combination all of the
310 Invariant Sections of all of the original documents, unmodified, and
311 list them all as Invariant Sections of your combined work in its
312 license notice, and that you preserve all their Warranty Disclaimers.
314 The combined work need only contain one copy of this License, and
315 multiple identical Invariant Sections may be replaced with a single
316 copy. If there are multiple Invariant Sections with the same name but
317 different contents, make the title of each such section unique by
318 adding at the end of it, in parentheses, the name of the original
319 author or publisher of that section if known, or else a unique number.
320 Make the same adjustment to the section titles in the list of
321 Invariant Sections in the license notice of the combined work.
323 In the combination, you must combine any sections Entitled ``History''
324 in the various original documents, forming one section Entitled
325 ``History''; likewise combine any sections Entitled ``Acknowledgements'',
326 and any sections Entitled ``Dedications''. You must delete all sections
327 Entitled ``Endorsements''.
329 \section{Collections of Documents}
331 You may make a collection consisting of the Document and other documents
332 released under this License, and replace the individual copies of this
333 License in the various documents with a single copy that is included in
334 the collection, provided that you follow the rules of this License for
335 verbatim copying of each of the documents in all other respects.
337 You may extract a single document from such a collection, and distribute
338 it individually under this License, provided you insert a copy of this
339 License into the extracted document, and follow this License in all
340 other respects regarding verbatim copying of that document.
342 \section{Aggregation With Independent Works}
344 A compilation of the Document or its derivatives with other separate
345 and independent documents or works, in or on a volume of a storage or
346 distribution medium, is called an ``aggregate'' if the copyright
347 resulting from the compilation is not used to limit the legal rights
348 of the compilation's users beyond what the individual works permit.
349 When the Document is included in an aggregate, this License does not
350 apply to the other works in the aggregate which are not themselves
351 derivative works of the Document.
353 If the Cover Text requirement of section~3 is applicable to these
354 copies of the Document, then if the Document is less than one half of
355 the entire aggregate, the Document's Cover Texts may be placed on
356 covers that bracket the Document within the aggregate, or the
357 electronic equivalent of covers if the Document is in electronic form.
358 Otherwise they must appear on printed covers that bracket the whole
361 \section{Translation}
363 Translation is considered a kind of modification, so you may
364 distribute translations of the Document under the terms of section~4.
365 Replacing Invariant Sections with translations requires special
366 permission from their copyright holders, but you may include
367 translations of some or all Invariant Sections in addition to the
368 original versions of these Invariant Sections. You may include a
369 translation of this License, and all the license notices in the
370 Document, and any Warranty Disclaimers, provided that you also include
371 the original English version of this License and the original versions
372 of those notices and disclaimers. In case of a disagreement between
373 the translation and the original version of this License or a notice
374 or disclaimer, the original version will prevail.
376 If a section in the Document is Entitled ``Acknowledgements'',
377 ``Dedications'', or ``History'', the requirement (section~4) to Preserve
378 its Title (section~1) will typically require changing the actual
382 \section{Termination}
384 You may not copy, modify, sublicense, or distribute the Document
385 except as expressly provided under this License. Any attempt
386 otherwise to copy, modify, sublicense, or distribute it is void, and
387 will automatically terminate your rights under this License.
389 However, if you cease all violation of this License, then your license
390 from a particular copyright holder is reinstated (a) provisionally,
391 unless and until the copyright holder explicitly and finally
392 terminates your license, and (b) permanently, if the copyright holder
393 fails to notify you of the violation by some reasonable means prior to
394 60 days after the cessation.
396 Moreover, your license from a particular copyright holder is
397 reinstated permanently if the copyright holder notifies you of the
398 violation by some reasonable means, this is the first time you have
399 received notice of violation of this License (for any work) from that
400 copyright holder, and you cure the violation prior to 30 days after
401 your receipt of the notice.
403 Termination of your rights under this section does not terminate the
404 licenses of parties who have received copies or rights from you under
405 this License. If your rights have been terminated and not permanently
406 reinstated, receipt of a copy of some or all of the same material does
407 not give you any rights to use it.
409 \section{Future Revisions of This License}
412 The Free Software Foundation may publish new, revised versions
413 of the GNU Free Documentation License from time to time. Such new
414 versions will be similar in spirit to the present version, but may
415 differ in detail to address new problems or concerns. See
416 \url{http://www.gnu.org/copyleft/}.
418 Each version of the License is given a distinguishing version number.
419 If the Document specifies that a particular numbered version of this
420 License ``or any later version'' applies to it, you have the option of
421 following the terms and conditions either of that specified version or
422 of any later version that has been published (not as a draft) by the
423 Free Software Foundation. If the Document does not specify a version
424 number of this License, you may choose any version ever published (not
425 as a draft) by the Free Software Foundation. If the Document
426 specifies that a proxy can decide which future versions of this
427 License can be used, that proxy's public statement of acceptance of a
428 version permanently authorizes you to choose that version for the
432 \section{Relicensing}
434 ``Massive Multiauthor Collaboration Site'' (or ``MMC Site'') means any
435 World Wide Web server that publishes copyrightable works and also
436 provides prominent facilities for anybody to edit those works. A
437 public wiki that anybody can edit is an example of such a server. A
438 ``Massive Multiauthor Collaboration'' (or ``MMC'') contained in the
439 site means any set of copyrightable works thus published on the MMC
442 ``CC-BY-SA'' means the Creative Commons Attribution-Share Alike 3.0
443 license published by Creative Commons Corporation, a not-for-profit
444 corporation with a principal place of business in San Francisco,
445 California, as well as future copyleft versions of that license
446 published by that same organization.
448 ``Incorporate'' means to publish or republish a Document, in whole or
449 in part, as part of another Document.
451 An MMC is ``eligible for relicensing'' if it is licensed under this
452 License, and if all works that were first published under this License
453 somewhere other than this MMC, and subsequently incorporated in whole
454 or in part into the MMC, (1) had no cover texts or invariant sections,
455 and (2) were thus incorporated prior to November 1, 2008.
457 The operator of an MMC Site may republish an MMC contained in the site
458 under CC-BY-SA on the same site at any time before August 1, 2009,
459 provided the MMC is eligible for relicensing.
461 \section{Addendum: How to use this License for your documents}
463 To use this License in a document you have written, include a copy of
464 the License in the document and put the following copyright and
465 license notices just after the title page:
469 Copyright \copyright{} YEAR YOUR NAME.
470 Permission is granted to copy, distribute and/or modify this document
471 under the terms of the GNU Free Documentation License, Version 1.3
472 or any later version published by the Free Software Foundation;
473 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
474 A copy of the license is included in the section entitled ``GNU
475 Free Documentation License''.
479 If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
480 replace the ``with \dots\ Texts.''\ line with this:
484 with the Invariant Sections being LIST THEIR TITLES, with the
485 Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
489 If you have Invariant Sections without Cover Texts, or some other
490 combination of the three, merge those two alternatives to suit the
493 If your document contains nontrivial examples of program code, we
494 recommend releasing these examples in parallel under your choice of
495 free software license, such as the GNU General Public License,
496 to permit their use in free software.