1@c The GNU Free Documentation License.
2@center Version 1.3, 3 November 2008
3
4@c This file is intended to be included within another document,
5@c hence no sectioning command or @node.
6
7@display
8Copyright @copyright{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
9@uref{http://fsf.org/}
10
11Everyone is permitted to copy and distribute verbatim copies
12of this license document, but changing it is not allowed.
13@end display
14
15@enumerate 0
16@item
17PREAMBLE
18
19The purpose of this License is to make a manual, textbook, or other
20functional and useful document @dfn{free} in the sense of freedom: to
21assure everyone the effective freedom to copy and redistribute it,
22with or without modifying it, either commercially or noncommercially.
23Secondarily, this License preserves for the author and publisher a way
24to get credit for their work, while not being considered responsible
25for modifications made by others.
26
27This License is a kind of ``copyleft'', which means that derivative
28works of the document must themselves be free in the same sense.  It
29complements the GNU General Public License, which is a copyleft
30license designed for free software.
31
32We have designed this License in order to use it for manuals for free
33software, because free software needs free documentation: a free
34program should come with manuals providing the same freedoms that the
35software does.  But this License is not limited to software manuals;
36it can be used for any textual work, regardless of subject matter or
37whether it is published as a printed book.  We recommend this License
38principally for works whose purpose is instruction or reference.
39
40@item
41APPLICABILITY AND DEFINITIONS
42
43This License applies to any manual or other work, in any medium, that
44contains a notice placed by the copyright holder saying it can be
45distributed under the terms of this License.  Such a notice grants a
46world-wide, royalty-free license, unlimited in duration, to use that
47work under the conditions stated herein.  The ``Document'', below,
48refers to any such manual or work.  Any member of the public is a
49licensee, and is addressed as ``you''.  You accept the license if you
50copy, modify or distribute the work in a way requiring permission
51under copyright law.
52
53A ``Modified Version'' of the Document means any work containing the
54Document or a portion of it, either copied verbatim, or with
55modifications and/or translated into another language.
56
57A ``Secondary Section'' is a named appendix or a front-matter section
58of the Document that deals exclusively with the relationship of the
59publishers or authors of the Document to the Document's overall
60subject (or to related matters) and contains nothing that could fall
61directly within that overall subject.  (Thus, if the Document is in
62part a textbook of mathematics, a Secondary Section may not explain
63any mathematics.)  The relationship could be a matter of historical
64connection with the subject or with related matters, or of legal,
65commercial, philosophical, ethical or political position regarding
66them.
67
68The ``Invariant Sections'' are certain Secondary Sections whose titles
69are designated, as being those of Invariant Sections, in the notice
70that says that the Document is released under this License.  If a
71section does not fit the above definition of Secondary then it is not
72allowed to be designated as Invariant.  The Document may contain zero
73Invariant Sections.  If the Document does not identify any Invariant
74Sections then there are none.
75
76The ``Cover Texts'' are certain short passages of text that are listed,
77as Front-Cover Texts or Back-Cover Texts, in the notice that says that
78the Document is released under this License.  A Front-Cover Text may
79be at most 5 words, and a Back-Cover Text may be at most 25 words.
80
81A ``Transparent'' copy of the Document means a machine-readable copy,
82represented in a format whose specification is available to the
83general public, that is suitable for revising the document
84straightforwardly with generic text editors or (for images composed of
85pixels) generic paint programs or (for drawings) some widely available
86drawing editor, and that is suitable for input to text formatters or
87for automatic translation to a variety of formats suitable for input
88to text formatters.  A copy made in an otherwise Transparent file
89format whose markup, or absence of markup, has been arranged to thwart
90or discourage subsequent modification by readers is not Transparent.
91An image format is not Transparent if used for any substantial amount
92of text.  A copy that is not ``Transparent'' is called ``Opaque''.
93
94Examples of suitable formats for Transparent copies include plain
95ASCII without markup, Texinfo input format, La@TeX{} input
96format, SGML or XML using a publicly available
97DTD, and standard-conforming simple HTML,
98PostScript or PDF designed for human modification.  Examples
99of transparent image formats include PNG, XCF and
100JPG.  Opaque formats include proprietary formats that can be
101read and edited only by proprietary word processors, SGML or
102XML for which the DTD and/or processing tools are
103not generally available, and the machine-generated HTML,
104PostScript or PDF produced by some word processors for
105output purposes only.
106
107The ``Title Page'' means, for a printed book, the title page itself,
108plus such following pages as are needed to hold, legibly, the material
109this License requires to appear in the title page.  For works in
110formats which do not have any title page as such, ``Title Page'' means
111the text near the most prominent appearance of the work's title,
112preceding the beginning of the body of the text.
113
114The ``publisher'' means any person or entity that distributes copies
115of the Document to the public.
116
117A section ``Entitled XYZ'' means a named subunit of the Document whose
118title either is precisely XYZ or contains XYZ in parentheses following
119text that translates XYZ in another language.  (Here XYZ stands for a
120specific section name mentioned below, such as ``Acknowledgements'',
121``Dedications'', ``Endorsements'', or ``History''.)  To ``Preserve the Title''
122of such a section when you modify the Document means that it remains a
123section ``Entitled XYZ'' according to this definition.
124
125The Document may include Warranty Disclaimers next to the notice which
126states that this License applies to the Document.  These Warranty
127Disclaimers are considered to be included by reference in this
128License, but only as regards disclaiming warranties: any other
129implication that these Warranty Disclaimers may have is void and has
130no effect on the meaning of this License.
131
132@item
133VERBATIM COPYING
134
135You may copy and distribute the Document in any medium, either
136commercially or noncommercially, provided that this License, the
137copyright notices, and the license notice saying this License applies
138to the Document are reproduced in all copies, and that you add no other
139conditions whatsoever to those of this License.  You may not use
140technical measures to obstruct or control the reading or further
141copying of the copies you make or distribute.  However, you may accept
142compensation in exchange for copies.  If you distribute a large enough
143number of copies you must also follow the conditions in section 3.
144
145You may also lend copies, under the same conditions stated above, and
146you may publicly display copies.
147
148@item
149COPYING IN QUANTITY
150
151If you publish printed copies (or copies in media that commonly have
152printed covers) of the Document, numbering more than 100, and the
153Document's license notice requires Cover Texts, you must enclose the
154copies in covers that carry, clearly and legibly, all these Cover
155Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
156the back cover.  Both covers must also clearly and legibly identify
157you as the publisher of these copies.  The front cover must present
158the full title with all words of the title equally prominent and
159visible.  You may add other material on the covers in addition.
160Copying with changes limited to the covers, as long as they preserve
161the title of the Document and satisfy these conditions, can be treated
162as verbatim copying in other respects.
163
164If the required texts for either cover are too voluminous to fit
165legibly, you should put the first ones listed (as many as fit
166reasonably) on the actual cover, and continue the rest onto adjacent
167pages.
168
169If you publish or distribute Opaque copies of the Document numbering
170more than 100, you must either include a machine-readable Transparent
171copy along with each Opaque copy, or state in or with each Opaque copy
172a computer-network location from which the general network-using
173public has access to download using public-standard network protocols
174a complete Transparent copy of the Document, free of added material.
175If you use the latter option, you must take reasonably prudent steps,
176when you begin distribution of Opaque copies in quantity, to ensure
177that this Transparent copy will remain thus accessible at the stated
178location until at least one year after the last time you distribute an
179Opaque copy (directly or through your agents or retailers) of that
180edition to the public.
181
182It is requested, but not required, that you contact the authors of the
183Document well before redistributing any large number of copies, to give
184them a chance to provide you with an updated version of the Document.
185
186@item
187MODIFICATIONS
188
189You may copy and distribute a Modified Version of the Document under
190the conditions of sections 2 and 3 above, provided that you release
191the Modified Version under precisely this License, with the Modified
192Version filling the role of the Document, thus licensing distribution
193and modification of the Modified Version to whoever possesses a copy
194of it.  In addition, you must do these things in the Modified Version:
195
196@enumerate A
197@item
198Use in the Title Page (and on the covers, if any) a title distinct
199from that of the Document, and from those of previous versions
200(which should, if there were any, be listed in the History section
201of the Document).  You may use the same title as a previous version
202if the original publisher of that version gives permission.
203
204@item
205List on the Title Page, as authors, one or more persons or entities
206responsible for authorship of the modifications in the Modified
207Version, together with at least five of the principal authors of the
208Document (all of its principal authors, if it has fewer than five),
209unless they release you from this requirement.
210
211@item
212State on the Title page the name of the publisher of the
213Modified Version, as the publisher.
214
215@item
216Preserve all the copyright notices of the Document.
217
218@item
219Add an appropriate copyright notice for your modifications
220adjacent to the other copyright notices.
221
222@item
223Include, immediately after the copyright notices, a license notice
224giving the public permission to use the Modified Version under the
225terms of this License, in the form shown in the Addendum below.
226
227@item
228Preserve in that license notice the full lists of Invariant Sections
229and required Cover Texts given in the Document's license notice.
230
231@item
232Include an unaltered copy of this License.
233
234@item
235Preserve the section Entitled ``History'', Preserve its Title, and add
236to it an item stating at least the title, year, new authors, and
237publisher of the Modified Version as given on the Title Page.  If
238there is no section Entitled ``History'' in the Document, create one
239stating the title, year, authors, and publisher of the Document as
240given on its Title Page, then add an item describing the Modified
241Version as stated in the previous sentence.
242
243@item
244Preserve the network location, if any, given in the Document for
245public access to a Transparent copy of the Document, and likewise
246the network locations given in the Document for previous versions
247it was based on.  These may be placed in the ``History'' section.
248You may omit a network location for a work that was published at
249least four years before the Document itself, or if the original
250publisher of the version it refers to gives permission.
251
252@item
253For any section Entitled ``Acknowledgements'' or ``Dedications'', Preserve
254the Title of the section, and preserve in the section all the
255substance and tone of each of the contributor acknowledgements and/or
256dedications given therein.
257
258@item
259Preserve all the Invariant Sections of the Document,
260unaltered in their text and in their titles.  Section numbers
261or the equivalent are not considered part of the section titles.
262
263@item
264Delete any section Entitled ``Endorsements''.  Such a section
265may not be included in the Modified Version.
266
267@item
268Do not retitle any existing section to be Entitled ``Endorsements'' or
269to conflict in title with any Invariant Section.
270
271@item
272Preserve any Warranty Disclaimers.
273@end enumerate
274
275If the Modified Version includes new front-matter sections or
276appendices that qualify as Secondary Sections and contain no material
277copied from the Document, you may at your option designate some or all
278of these sections as invariant.  To do this, add their titles to the
279list of Invariant Sections in the Modified Version's license notice.
280These titles must be distinct from any other section titles.
281
282You may add a section Entitled ``Endorsements'', provided it contains
283nothing but endorsements of your Modified Version by various
284parties---for example, statements of peer review or that the text has
285been approved by an organization as the authoritative definition of a
286standard.
287
288You may add a passage of up to five words as a Front-Cover Text, and a
289passage of up to 25 words as a Back-Cover Text, to the end of the list
290of Cover Texts in the Modified Version.  Only one passage of
291Front-Cover Text and one of Back-Cover Text may be added by (or
292through arrangements made by) any one entity.  If the Document already
293includes a cover text for the same cover, previously added by you or
294by arrangement made by the same entity you are acting on behalf of,
295you may not add another; but you may replace the old one, on explicit
296permission from the previous publisher that added the old one.
297
298The author(s) and publisher(s) of the Document do not by this License
299give permission to use their names for publicity for or to assert or
300imply endorsement of any Modified Version.
301
302@item
303COMBINING DOCUMENTS
304
305You may combine the Document with other documents released under this
306License, under the terms defined in section 4 above for modified
307versions, provided that you include in the combination all of the
308Invariant Sections of all of the original documents, unmodified, and
309list them all as Invariant Sections of your combined work in its
310license notice, and that you preserve all their Warranty Disclaimers.
311
312The combined work need only contain one copy of this License, and
313multiple identical Invariant Sections may be replaced with a single
314copy.  If there are multiple Invariant Sections with the same name but
315different contents, make the title of each such section unique by
316adding at the end of it, in parentheses, the name of the original
317author or publisher of that section if known, or else a unique number.
318Make the same adjustment to the section titles in the list of
319Invariant Sections in the license notice of the combined work.
320
321In the combination, you must combine any sections Entitled ``History''
322in the various original documents, forming one section Entitled
323``History''; likewise combine any sections Entitled ``Acknowledgements'',
324and any sections Entitled ``Dedications''.  You must delete all
325sections Entitled ``Endorsements.''
326
327@item
328COLLECTIONS OF DOCUMENTS
329
330You may make a collection consisting of the Document and other documents
331released under this License, and replace the individual copies of this
332License in the various documents with a single copy that is included in
333the collection, provided that you follow the rules of this License for
334verbatim copying of each of the documents in all other respects.
335
336You may extract a single document from such a collection, and distribute
337it individually under this License, provided you insert a copy of this
338License into the extracted document, and follow this License in all
339other respects regarding verbatim copying of that document.
340
341@item
342AGGREGATION WITH INDEPENDENT WORKS
343
344A compilation of the Document or its derivatives with other separate
345and independent documents or works, in or on a volume of a storage or
346distribution medium, is called an ``aggregate'' if the copyright
347resulting from the compilation is not used to limit the legal rights
348of the compilation's users beyond what the individual works permit.
349When the Document is included in an aggregate, this License does not
350apply to the other works in the aggregate which are not themselves
351derivative works of the Document.
352
353If the Cover Text requirement of section 3 is applicable to these
354copies of the Document, then if the Document is less than one half of
355the entire aggregate, the Document's Cover Texts may be placed on
356covers that bracket the Document within the aggregate, or the
357electronic equivalent of covers if the Document is in electronic form.
358Otherwise they must appear on printed covers that bracket the whole
359aggregate.
360
361@item
362TRANSLATION
363
364Translation is considered a kind of modification, so you may
365distribute translations of the Document under the terms of section 4.
366Replacing Invariant Sections with translations requires special
367permission from their copyright holders, but you may include
368translations of some or all Invariant Sections in addition to the
369original versions of these Invariant Sections.  You may include a
370translation of this License, and all the license notices in the
371Document, and any Warranty Disclaimers, provided that you also include
372the original English version of this License and the original versions
373of those notices and disclaimers.  In case of a disagreement between
374the translation and the original version of this License or a notice
375or disclaimer, the original version will prevail.
376
377If a section in the Document is Entitled ``Acknowledgements'',
378``Dedications'', or ``History'', the requirement (section 4) to Preserve
379its Title (section 1) will typically require changing the actual
380title.
381
382@item
383TERMINATION
384
385You may not copy, modify, sublicense, or distribute the Document
386except as expressly provided under this License.  Any attempt
387otherwise to copy, modify, sublicense, or distribute it is void, and
388will automatically terminate your rights under this License.
389
390However, if you cease all violation of this License, then your license
391from a particular copyright holder is reinstated (a) provisionally,
392unless and until the copyright holder explicitly and finally
393terminates your license, and (b) permanently, if the copyright holder
394fails to notify you of the violation by some reasonable means prior to
39560 days after the cessation.
396
397Moreover, your license from a particular copyright holder is
398reinstated permanently if the copyright holder notifies you of the
399violation by some reasonable means, this is the first time you have
400received notice of violation of this License (for any work) from that
401copyright holder, and you cure the violation prior to 30 days after
402your receipt of the notice.
403
404Termination of your rights under this section does not terminate the
405licenses of parties who have received copies or rights from you under
406this License.  If your rights have been terminated and not permanently
407reinstated, receipt of a copy of some or all of the same material does
408not give you any rights to use it.
409
410@item
411FUTURE REVISIONS OF THIS LICENSE
412
413The Free Software Foundation may publish new, revised versions
414of the GNU Free Documentation License from time to time.  Such new
415versions will be similar in spirit to the present version, but may
416differ in detail to address new problems or concerns.  See
417@uref{http://www.gnu.org/copyleft/}.
418
419Each version of the License is given a distinguishing version number.
420If the Document specifies that a particular numbered version of this
421License ``or any later version'' applies to it, you have the option of
422following the terms and conditions either of that specified version or
423of any later version that has been published (not as a draft) by the
424Free Software Foundation.  If the Document does not specify a version
425number of this License, you may choose any version ever published (not
426as a draft) by the Free Software Foundation.  If the Document
427specifies that a proxy can decide which future versions of this
428License can be used, that proxy's public statement of acceptance of a
429version permanently authorizes you to choose that version for the
430Document.
431
432@item
433RELICENSING
434
435``Massive Multiauthor Collaboration Site'' (or ``MMC Site'') means any
436World Wide Web server that publishes copyrightable works and also
437provides prominent facilities for anybody to edit those works.  A
438public wiki that anybody can edit is an example of such a server.  A
439``Massive Multiauthor Collaboration'' (or ``MMC'') contained in the
440site means any set of copyrightable works thus published on the MMC
441site.
442
443``CC-BY-SA'' means the Creative Commons Attribution-Share Alike 3.0
444license published by Creative Commons Corporation, a not-for-profit
445corporation with a principal place of business in San Francisco,
446California, as well as future copyleft versions of that license
447published by that same organization.
448
449``Incorporate'' means to publish or republish a Document, in whole or
450in part, as part of another Document.
451
452An MMC is ``eligible for relicensing'' if it is licensed under this
453License, and if all works that were first published under this License
454somewhere other than this MMC, and subsequently incorporated in whole
455or in part into the MMC, (1) had no cover texts or invariant sections,
456and (2) were thus incorporated prior to November 1, 2008.
457
458The operator of an MMC Site may republish an MMC contained in the site
459under CC-BY-SA on the same site at any time before August 1, 2009,
460provided the MMC is eligible for relicensing.
461
462@end enumerate
463
464@page
465@heading ADDENDUM: How to use this License for your documents
466
467To use this License in a document you have written, include a copy of
468the License in the document and put the following copyright and
469license notices just after the title page:
470
471@smallexample
472@group
473  Copyright (C)  @var{year}  @var{your name}.
474  Permission is granted to copy, distribute and/or modify this document
475  under the terms of the GNU Free Documentation License, Version 1.3
476  or any later version published by the Free Software Foundation;
477  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
478  Texts.  A copy of the license is included in the section entitled ``GNU
479  Free Documentation License''.
480@end group
481@end smallexample
482
483If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
484replace the ``with@dots{}Texts.''@: line with this:
485
486@smallexample
487@group
488    with the Invariant Sections being @var{list their titles}, with
489    the Front-Cover Texts being @var{list}, and with the Back-Cover Texts
490    being @var{list}.
491@end group
492@end smallexample
493
494If you have Invariant Sections without Cover Texts, or some other
495combination of the three, merge those two alternatives to suit the
496situation.
497
498If your document contains nontrivial examples of program code, we
499recommend releasing these examples in parallel under your choice of
500free software license, such as the GNU General Public License,
501to permit their use in free software.
502
503@c Local Variables:
504@c ispell-local-pdict: "ispell-dict"
505@c End:
506