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{} 2000-2002, 2007-2008, 2010-2011 Free Software 9Foundation, Inc. 10@uref{http://fsf.org/} 11 12Everyone is permitted to copy and distribute verbatim copies 13of this license document, but changing it is not allowed. 14@end display 15 16@enumerate 0 17@item 18PREAMBLE 19 20The purpose of this License is to make a manual, textbook, or other 21functional and useful document @dfn{free} in the sense of freedom: to 22assure everyone the effective freedom to copy and redistribute it, 23with or without modifying it, either commercially or noncommercially. 24Secondarily, this License preserves for the author and publisher a way 25to get credit for their work, while not being considered responsible 26for modifications made by others. 27 28This License is a kind of ``copyleft'', which means that derivative 29works of the document must themselves be free in the same sense. It 30complements the GNU General Public License, which is a copyleft 31license designed for free software. 32 33We have designed this License in order to use it for manuals for free 34software, because free software needs free documentation: a free 35program should come with manuals providing the same freedoms that the 36software does. But this License is not limited to software manuals; 37it can be used for any textual work, regardless of subject matter or 38whether it is published as a printed book. We recommend this License 39principally for works whose purpose is instruction or reference. 40 41@item 42APPLICABILITY AND DEFINITIONS 43 44This License applies to any manual or other work, in any medium, that 45contains a notice placed by the copyright holder saying it can be 46distributed under the terms of this License. Such a notice grants a 47world-wide, royalty-free license, unlimited in duration, to use that 48work under the conditions stated herein. The ``Document'', below, 49refers to any such manual or work. Any member of the public is a 50licensee, and is addressed as ``you''. You accept the license if you 51copy, modify or distribute the work in a way requiring permission 52under copyright law. 53 54A ``Modified Version'' of the Document means any work containing the 55Document or a portion of it, either copied verbatim, or with 56modifications and/or translated into another language. 57 58A ``Secondary Section'' is a named appendix or a front-matter section 59of the Document that deals exclusively with the relationship of the 60publishers or authors of the Document to the Document's overall 61subject (or to related matters) and contains nothing that could fall 62directly within that overall subject. (Thus, if the Document is in 63part a textbook of mathematics, a Secondary Section may not explain 64any mathematics.) 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A copy that is not ``Transparent'' is called ``Opaque''. 94 95Examples of suitable formats for Transparent copies include plain 96@sc{ascii} without markup, Texinfo input format, La@TeX{} input 97format, @acronym{SGML} or @acronym{XML} using a publicly available 98@acronym{DTD}, and standard-conforming simple @acronym{HTML}, 99PostScript or @acronym{PDF} designed for human modification. Examples 100of transparent image formats include @acronym{PNG}, @acronym{XCF} and 101@acronym{JPG}. 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For works in 111formats which do not have any title page as such, ``Title Page'' means 112the text near the most prominent appearance of the work's title, 113preceding the beginning of the body of the text. 114 115The ``publisher'' means any person or entity that distributes copies 116of the Document to the public. 117 118A section ``Entitled XYZ'' means a named subunit of the Document whose 119title either is precisely XYZ or contains XYZ in parentheses following 120text that translates XYZ in another language. (Here XYZ stands for a 121specific section name mentioned below, such as ``Acknowledgements'', 122``Dedications'', ``Endorsements'', or ``History''.) To ``Preserve the Title'' 123of such a section when you modify the Document means that it remains a 124section ``Entitled XYZ'' according to this definition. 125 126The Document may include Warranty Disclaimers next to the notice which 127states that this License applies to the Document. 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You may add other material on the covers in addition. 161Copying with changes limited to the covers, as long as they preserve 162the title of the Document and satisfy these conditions, can be treated 163as verbatim copying in other respects. 164 165If the required texts for either cover are too voluminous to fit 166legibly, you should put the first ones listed (as many as fit 167reasonably) on the actual cover, and continue the rest onto adjacent 168pages. 169 170If you publish or distribute Opaque copies of the Document numbering 171more than 100, you must either include a machine-readable Transparent 172copy along with each Opaque copy, or state in or with each Opaque copy 173a computer-network location from which the general network-using 174public has access to download using public-standard network protocols 175a complete Transparent copy of the Document, free of added material. 176If you use the latter option, you must take reasonably prudent steps, 177when you begin distribution of Opaque copies in quantity, to ensure 178that this Transparent copy will remain thus accessible at the stated 179location until at least one year after the last time you distribute an 180Opaque copy (directly or through your agents or retailers) of that 181edition to the public. 182 183It is requested, but not required, that you contact the authors of the 184Document well before redistributing any large number of copies, to give 185them a chance to provide you with an updated version of the Document. 186 187@item 188MODIFICATIONS 189 190You may copy and distribute a Modified Version of the Document under 191the conditions of sections 2 and 3 above, provided that you release 192the Modified Version under precisely this License, with the Modified 193Version filling the role of the Document, thus licensing distribution 194and modification of the Modified Version to whoever possesses a copy 195of it. In addition, you must do these things in the Modified Version: 196 197@enumerate A 198@item 199Use in the Title Page (and on the covers, if any) a title distinct 200from that of the Document, and from those of previous versions 201(which should, if there were any, be listed in the History section 202of the Document). You may use the same title as a previous version 203if the original publisher of that version gives permission. 204 205@item 206List on the Title Page, as authors, one or more persons or entities 207responsible for authorship of the modifications in the Modified 208Version, together with at least five of the principal authors of the 209Document (all of its principal authors, if it has fewer than five), 210unless they release you from this requirement. 211 212@item 213State on the Title page the name of the publisher of the 214Modified Version, as the publisher. 215 216@item 217Preserve all the copyright notices of the Document. 218 219@item 220Add an appropriate copyright notice for your modifications 221adjacent to the other copyright notices. 222 223@item 224Include, immediately after the copyright notices, a license notice 225giving the public permission to use the Modified Version under the 226terms of this License, in the form shown in the Addendum below. 227 228@item 229Preserve in that license notice the full lists of Invariant Sections 230and required Cover Texts given in the Document's license notice. 231 232@item 233Include an unaltered copy of this License. 234 235@item 236Preserve the section Entitled ``History'', Preserve its Title, and add 237to it an item stating at least the title, year, new authors, and 238publisher of the Modified Version as given on the Title Page. If 239there is no section Entitled ``History'' in the Document, create one 240stating the title, year, authors, and publisher of the Document as 241given on its Title Page, then add an item describing the Modified 242Version as stated in the previous sentence. 243 244@item 245Preserve the network location, if any, given in the Document for 246public access to a Transparent copy of the Document, and likewise 247the network locations given in the Document for previous versions 248it was based on. These may be placed in the ``History'' section. 249You may omit a network location for a work that was published at 250least four years before the Document itself, or if the original 251publisher of the version it refers to gives permission. 252 253@item 254For any section Entitled ``Acknowledgements'' or ``Dedications'', Preserve 255the Title of the section, and preserve in the section all the 256substance and tone of each of the contributor acknowledgements and/or 257dedications given therein. 258 259@item 260Preserve all the Invariant Sections of the Document, 261unaltered in their text and in their titles. Section numbers 262or the equivalent are not considered part of the section titles. 263 264@item 265Delete any section Entitled ``Endorsements''. Such a section 266may not be included in the Modified Version. 267 268@item 269Do not retitle any existing section to be Entitled ``Endorsements'' or 270to conflict in title with any Invariant Section. 271 272@item 273Preserve any Warranty Disclaimers. 274@end enumerate 275 276If the Modified Version includes new front-matter sections or 277appendices that qualify as Secondary Sections and contain no material 278copied from the Document, you may at your option designate some or all 279of these sections as invariant. To do this, add their titles to the 280list of Invariant Sections in the Modified Version's license notice. 281These titles must be distinct from any other section titles. 282 283You may add a section Entitled ``Endorsements'', provided it contains 284nothing but endorsements of your Modified Version by various 285parties---for example, statements of peer review or that the text has 286been approved by an organization as the authoritative definition of a 287standard. 288 289You may add a passage of up to five words as a Front-Cover Text, and a 290passage of up to 25 words as a Back-Cover Text, to the end of the list 291of Cover Texts in the Modified Version. Only one passage of 292Front-Cover Text and one of Back-Cover Text may be added by (or 293through arrangements made by) any one entity. If the Document already 294includes a cover text for the same cover, previously added by you or 295by arrangement made by the same entity you are acting on behalf of, 296you may not add another; but you may replace the old one, on explicit 297permission from the previous publisher that added the old one. 298 299The author(s) and publisher(s) of the Document do not by this License 300give permission to use their names for publicity for or to assert or 301imply endorsement of any Modified Version. 302 303@item 304COMBINING DOCUMENTS 305 306You may combine the Document with other documents released under this 307License, under the terms defined in section 4 above for modified 308versions, provided that you include in the combination all of the 309Invariant Sections of all of the original documents, unmodified, and 310list them all as Invariant Sections of your combined work in its 311license notice, and that you preserve all their Warranty Disclaimers. 312 313The combined work need only contain one copy of this License, and 314multiple identical Invariant Sections may be replaced with a single 315copy. If there are multiple Invariant Sections with the same name but 316different contents, make the title of each such section unique by 317adding at the end of it, in parentheses, the name of the original 318author or publisher of that section if known, or else a unique number. 319Make the same adjustment to the section titles in the list of 320Invariant Sections in the license notice of the combined work. 321 322In the combination, you must combine any sections Entitled ``History'' 323in the various original documents, forming one section Entitled 324``History''; likewise combine any sections Entitled ``Acknowledgements'', 325and any sections Entitled ``Dedications''. You must delete all 326sections Entitled ``Endorsements.'' 327 328@item 329COLLECTIONS OF DOCUMENTS 330 331You may make a collection consisting of the Document and other documents 332released under this License, and replace the individual copies of this 333License in the various documents with a single copy that is included in 334the collection, provided that you follow the rules of this License for 335verbatim copying of each of the documents in all other respects. 336 337You may extract a single document from such a collection, and distribute 338it individually under this License, provided you insert a copy of this 339License into the extracted document, and follow this License in all 340other respects regarding verbatim copying of that document. 341 342@item 343AGGREGATION WITH INDEPENDENT WORKS 344 345A compilation of the Document or its derivatives with other separate 346and independent documents or works, in or on a volume of a storage or 347distribution medium, is called an ``aggregate'' if the copyright 348resulting from the compilation is not used to limit the legal rights 349of the compilation's users beyond what the individual works permit. 350When the Document is included in an aggregate, this License does not 351apply to the other works in the aggregate which are not themselves 352derivative works of the Document. 353 354If the Cover Text requirement of section 3 is applicable to these 355copies of the Document, then if the Document is less than one half of 356the entire aggregate, the Document's Cover Texts may be placed on 357covers that bracket the Document within the aggregate, or the 358electronic equivalent of covers if the Document is in electronic form. 359Otherwise they must appear on printed covers that bracket the whole 360aggregate. 361 362@item 363TRANSLATION 364 365Translation is considered a kind of modification, so you may 366distribute translations of the Document under the terms of section 4. 367Replacing Invariant Sections with translations requires special 368permission from their copyright holders, but you may include 369translations of some or all Invariant Sections in addition to the 370original versions of these Invariant Sections. You may include a 371translation of this License, and all the license notices in the 372Document, and any Warranty Disclaimers, provided that you also include 373the original English version of this License and the original versions 374of those notices and disclaimers. In case of a disagreement between 375the translation and the original version of this License or a notice 376or disclaimer, the original version will prevail. 377 378If a section in the Document is Entitled ``Acknowledgements'', 379``Dedications'', or ``History'', the requirement (section 4) to Preserve 380its Title (section 1) will typically require changing the actual 381title. 382 383@item 384TERMINATION 385 386You may not copy, modify, sublicense, or distribute the Document 387except as expressly provided under this License. Any attempt 388otherwise to copy, modify, sublicense, or distribute it is void, and 389will automatically terminate your rights under this License. 390 391However, if you cease all violation of this License, then your license 392from a particular copyright holder is reinstated (a) provisionally, 393unless and until the copyright holder explicitly and finally 394terminates your license, and (b) permanently, if the copyright holder 395fails to notify you of the violation by some reasonable means prior to 39660 days after the cessation. 397 398Moreover, your license from a particular copyright holder is 399reinstated permanently if the copyright holder notifies you of the 400violation by some reasonable means, this is the first time you have 401received notice of violation of this License (for any work) from that 402copyright holder, and you cure the violation prior to 30 days after 403your receipt of the notice. 404 405Termination of your rights under this section does not terminate the 406licenses of parties who have received copies or rights from you under 407this License. If your rights have been terminated and not permanently 408reinstated, receipt of a copy of some or all of the same material does 409not give you any rights to use it. 410 411@item 412FUTURE REVISIONS OF THIS LICENSE 413 414The Free Software Foundation may publish new, revised versions 415of the GNU Free Documentation License from time to time. Such new 416versions will be similar in spirit to the present version, but may 417differ in detail to address new problems or concerns. See 418@uref{http://www.gnu.org/copyleft/}. 419 420Each version of the License is given a distinguishing version number. 421If the Document specifies that a particular numbered version of this 422License ``or any later version'' applies to it, you have the option of 423following the terms and conditions either of that specified version or 424of any later version that has been published (not as a draft) by the 425Free Software Foundation. If the Document does not specify a version 426number of this License, you may choose any version ever published (not 427as a draft) by the Free Software Foundation. If the Document 428specifies that a proxy can decide which future versions of this 429License can be used, that proxy's public statement of acceptance of a 430version permanently authorizes you to choose that version for the 431Document. 432 433@item 434RELICENSING 435 436``Massive Multiauthor Collaboration Site'' (or ``MMC Site'') means any 437World Wide Web server that publishes copyrightable works and also 438provides prominent facilities for anybody to edit those works. A 439public wiki that anybody can edit is an example of such a server. A 440``Massive Multiauthor Collaboration'' (or ``MMC'') contained in the 441site means any set of copyrightable works thus published on the MMC 442site. 443 444``CC-BY-SA'' means the Creative Commons Attribution-Share Alike 3.0 445license published by Creative Commons Corporation, a not-for-profit 446corporation with a principal place of business in San Francisco, 447California, as well as future copyleft versions of that license 448published by that same organization. 449 450``Incorporate'' means to publish or republish a Document, in whole or 451in part, as part of another Document. 452 453An MMC is ``eligible for relicensing'' if it is licensed under this 454License, and if all works that were first published under this License 455somewhere other than this MMC, and subsequently incorporated in whole 456or in part into the MMC, (1) had no cover texts or invariant sections, 457and (2) were thus incorporated prior to November 1, 2008. 458 459The operator of an MMC Site may republish an MMC contained in the site 460under CC-BY-SA on the same site at any time before August 1, 2009, 461provided the MMC is eligible for relicensing. 462 463@end enumerate 464 465@page 466@heading ADDENDUM: How to use this License for your documents 467 468To use this License in a document you have written, include a copy of 469the License in the document and put the following copyright and 470license notices just after the title page: 471 472@smallexample 473@group 474 Copyright (C) @var{year} @var{your name}. 475 Permission is granted to copy, distribute and/or modify this document 476 under the terms of the GNU Free Documentation License, Version 1.3 477 or any later version published by the Free Software Foundation; 478 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover 479 Texts. A copy of the license is included in the section entitled ``GNU 480 Free Documentation License''. 481@end group 482@end smallexample 483 484If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, 485replace the ``with@dots{}Texts.'' line with this: 486 487@smallexample 488@group 489 with the Invariant Sections being @var{list their titles}, with 490 the Front-Cover Texts being @var{list}, and with the Back-Cover Texts 491 being @var{list}. 492@end group 493@end smallexample 494 495If you have Invariant Sections without Cover Texts, or some other 496combination of the three, merge those two alternatives to suit the 497situation. 498 499If your document contains nontrivial examples of program code, we 500recommend releasing these examples in parallel under your choice of 501free software license, such as the GNU General Public License, 502to permit their use in free software. 503 504@c Local Variables: 505@c ispell-local-pdict: "ispell-dict" 506@c End: 507