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GNU Free Documentation License

GNU Free Documentation Licens

Version 1.1, March 200

Copyright (C) 2000 Free Software Foundation, Inc 59 Temple Place, Suite 330, Boston, MA 02111-1307 US

Everyone is permitted to copy and distribute verbatim copie of this license document, but changing it is not allowed


The purpose of this License is to make a manual, textbook, or othe written document "free" in the sense of freedom: to assure everyon the effective freedom to copy and redistribute it, with or withou modifying it, either commercially or noncommercially. Secondarily this License preserves for the author and publisher a way to ge credit for their work, while not being considered responsible fo modifications made by others

This License is a kind of "copyleft", which means that derivativ works of the document must themselves be free in the same sense. I complements the GNU General Public License, which is a copylef license designed for free software

We have designed this License in order to use it for manuals for fre software, because free software needs free documentation: a fre program should come with manuals providing the same freedoms that th software does. But this License is not limited to software manuals it can be used for any textual work, regardless of subject matter o whether it is published as a printed book. We recommend this Licens principally for works whose purpose is instruction or reference


This License applies to any manual or other work that contains notice placed by the copyright holder saying it can be distribute under the terms of this License. The "Document", below, refers to an such manual or work. Any member of the public is a licensee, and i addressed as "you"

A "Modified Version" of the Document means any work containing th Document or a portion of it, either copied verbatim, or wit modifications and/or translated into another language

A "Secondary Section" is a named appendix or a front-matter section o the Document that deals exclusively with the relationship of th publishers or authors of the Document to the Document's overall subjec (or to related matters) and contains nothing that could fall directl within that overall subject. (For example, if the Document is in part textbook of mathematics, a Secondary Section may not explain an mathematics.) The relationship could be a matter of historica connection with the subject or with related matters, or of legal commercial, philosophical, ethical or political position regardin them

The "Invariant Sections" are certain Secondary Sections whose title are designated, as being those of Invariant Sections, in the notic that says that the Document is released under this License

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 tha the Document is released under this License

A "Transparent" copy of the Document means a machine-readable copy represented in a format whose specification is available to th general public, whose contents can be viewed and edited directly an straightforwardly with generic text editors or (for images composed o pixels) generic paint programs or (for drawings) some widely availabl drawing editor, and that is suitable for input to text formatters o for automatic translation to a variety of formats suitable for inpu to text formatters. A copy made in an otherwise Transparent fil format whose markup has been designed to thwart or discourag subsequent modification by readers is not Transparent. A copy that i not "Transparent" is called "Opaque"

Examples of suitable formats for Transparent copies include plai ASCII without markup, Texinfo input format, LaTeX input format, SGM or XML using a publicly available DTD, and standard-conforming simpl HTML designed for human modification. Opaque formats includ PostScript, PDF, proprietary formats that can be read and edited onl by proprietary word processors, SGML or XML for which the DTD and/o processing tools are not generally available, and th machine-generated HTML produced by some word processors for outpu 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 materia this License requires to appear in the title page. For works i formats which do not have any title page as such, "Title Page" mean the text near the most prominent appearance of the work's title preceding the beginning of the body of the text


You may copy and distribute the Document in any medium, eithe commercially or noncommercially, provided that this License, th copyright notices, and the license notice saying this License applie to the Document are reproduced in all copies, and that you add no othe conditions whatsoever to those of this License. You may not us technical measures to obstruct or control the reading or furthe copying of the copies you make or distribute. However, you may accep compensation in exchange for copies. If you distribute a large enoug number of copies you must also follow the conditions in section 3

You may also lend copies, under the same conditions stated above, an you may publicly display copies


If you publish printed copies of the Document numbering more than 100 and the Document's license notice requires Cover Texts, you must enclos the copies in covers that carry, clearly and legibly, all these Cove Texts: Front-Cover Texts on the front cover, and Back-Cover Texts o the back cover. Both covers must also clearly and legibly identif you as the publisher of these copies. The front cover must presen the full title with all words of the title equally prominent an visible. You may add other material on the covers in addition Copying with changes limited to the covers, as long as they preserv the title of the Document and satisfy these conditions, can be treate as verbatim copying in other respects

If the required texts for either cover are too voluminous to fi legibly, you should put the first ones listed (as many as fi reasonably) on the actual cover, and continue the rest onto adjacen pages

If you publish or distribute Opaque copies of the Document numberin more than 100, you must either include a machine-readable Transparen copy along with each Opaque copy, or state in or with each Opaque cop a publicly-accessible computer-network location containing a complet Transparent copy of the Document, free of added material, which th general network-using public has access to download anonymously at n charge using public-standard network protocols. If you use the latte option, you must take reasonably prudent steps, when you begi distribution of Opaque copies in quantity, to ensure that thi Transparent copy will remain thus accessible at the stated locatio until at least one year after the last time you distribute an Opaqu copy (directly or through your agents or retailers) of that edition t the public

It is requested, but not required, that you contact the authors of th Document well before redistributing any large number of copies, to giv them a chance to provide you with an updated version of the Document


You may copy and distribute a Modified Version of the Document unde the conditions of sections 2 and 3 above, provided that you releas the Modified Version under precisely this License, with the Modifie Version filling the role of the Document, thus licensing distributio and modification of the Modified Version to whoever possesses a cop 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 distinc from that of the Document, and from those of previous version (which should, if there were any, be listed in the History sectio of the Document). You may use the same title as a previous versio if the original publisher of that version gives permission B. List on the Title Page, as authors, one or more persons or entitie responsible for authorship of the modifications in the Modifie Version, together with at least five of the principal authors of th Document (all of its principal authors, if it has less than five) C. State on the Title page the name of the publisher of th Modified Version, as the publisher D. Preserve all the copyright notices of the Document E. Add an appropriate copyright notice for your modification adjacent to the other copyright notices F. Include, immediately after the copyright notices, a license notic giving the public permission to use the Modified Version under th terms of this License, in the form shown in the Addendum below G. Preserve in that license notice the full lists of Invariant Section 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", and its title, and add t it an item stating at least the title, year, new authors, an publisher of the Modified Version as given on the Title Page. I there is no section entitled "History" in the Document, create on stating the title, year, authors, and publisher of the Document a given on its Title Page, then add an item describing the Modifie Version as stated in the previous sentence J. Preserve the network location, if any, given in the Document fo public access to a Transparent copy of the Document, and likewis the network locations given in the Document for previous version it was based on. These may be placed in the "History" section You may omit a network location for a work that was published a least four years before the Document itself, or if the origina publisher of the version it refers to gives permission K. In any section entitled "Acknowledgements" or "Dedications" preserve the section's title, and preserve in the section all th substance and tone of each of the contributor acknowledgement and/or dedications given therein L. Preserve all the Invariant Sections of the Document unaltered in their text and in their titles. Section number or the equivalent are not considered part of the section titles M. Delete any section entitled "Endorsements". Such a sectio may not be included in the Modified Version N. Do not retitle any existing section as "Endorsements or to conflict in title with any Invariant Section

If the Modified Version includes new front-matter sections o appendices that qualify as Secondary Sections and contain no materia copied from the Document, you may at your option designate some or al of these sections as invariant. To do this, add their titles to th 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 contain nothing but endorsements of your Modified Version by variou parties--for example, statements of peer review or that the text ha been approved by an organization as the authoritative definition of standard

You may add a passage of up to five words as a Front-Cover Text, and passage of up to 25 words as a Back-Cover Text, to the end of the lis of Cover Texts in the Modified Version. Only one passage o Front-Cover Text and one of Back-Cover Text may be added by (o through arrangements made by) any one entity. If the Document alread includes a cover text for the same cover, previously added by you o 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 explici permission from the previous publisher that added the old one

The author(s) and publisher(s) of the Document do not by this Licens give permission to use their names for publicity for or to assert o imply endorsement of any Modified Version


You may combine the Document with other documents released under thi License, under the terms defined in section 4 above for modifie versions, provided that you include in the combination all of th Invariant Sections of all of the original documents, unmodified, an list them all as Invariant Sections of your combined work in it license notice

The combined work need only contain one copy of this License, an multiple identical Invariant Sections may be replaced with a singl copy. If there are multiple Invariant Sections with the same name bu different contents, make the title of each such section unique b adding at the end of it, in parentheses, the name of the origina author or publisher of that section if known, or else a unique number Make the same adjustment to the section titles in the list o 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 entitle "History"; likewise combine any sections entitled "Acknowledgements" and any sections entitled "Dedications". You must delete all section entitled "Endorsements.


You may make a collection consisting of the Document and other document released under this License, and replace the individual copies of thi License in the various documents with a single copy that is included i the collection, provided that you follow the rules of this License fo verbatim copying of each of the documents in all other respects

You may extract a single document from such a collection, and distribut it individually under this License, provided you insert a copy of thi License into the extracted document, and follow this License in al other respects regarding verbatim copying of that document


A compilation of the Document or its derivatives with other separat and independent documents or works, in or on a volume of a storage o distribution medium, does not as a whole count as a Modified Versio of the Document, provided no compilation copyright is claimed for th compilation. Such a compilation is called an "aggregate", and thi License does not apply to the other self-contained works thus compile with the Document, on account of their being thus compiled, if the are not themselves derivative works of the Document

If the Cover Text requirement of section 3 is applicable to thes copies of the Document, then if the Document is less than one quarte of the entire aggregate, the Document's Cover Texts may be placed o covers that surround only the Document within the aggregate Otherwise they must appear on covers around the whole aggregate


Translation is considered a kind of modification, so you ma distribute translations of the Document under the terms of section 4 Replacing Invariant Sections with translations requires specia permission from their copyright holders, but you may includ translations of some or all Invariant Sections in addition to th original versions of these Invariant Sections. You may include translation of this License provided that you also include th original English version of this License. In case of a disagreemen between the translation and the original English version of thi License, the original English version will prevail


You may not copy, modify, sublicense, or distribute the Document excep as expressly provided for under this License. Any other attempt t copy, modify, sublicense or distribute the Document is void, and wil automatically terminate your rights under this License. However parties who have received copies, or rights, from you under thi License will not have their licenses terminated so long as suc parties remain in full compliance


The Free Software Foundation may publish new, revised version of the GNU Free Documentation License from time to time. Such ne versions will be similar in spirit to the present version, but ma differ in detail to address new problems or concerns. Se http://www.gnu.org/copyleft/

Each version of the License is given a distinguishing version number If the Document specifies that a particular numbered version of thi License "or any later version" applies to it, you have the option o following the terms and conditions either of that specified version o of any later version that has been published (not as a draft) by th Free Software Foundation. If the Document does not specify a versio number of this License, you may choose any version ever published (no as a draft) by the Free Software Foundation

ADDENDUM: How to use this License for your document

To use this License in a document you have written, include a copy o the License in the document and put the following copyright an license notices just after the title page

    Copyright (c)  YEAR  YOUR NAME
    Permission is granted to copy, distribute and/or modify this documen
    under the terms of the GNU Free Documentation License, Version 1.
    or any later version published by the Free Software Foundation
    with the Invariant Sections being LIST THEIR TITLES, with th
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST
    A copy of the license is included in the section entitled "GN
    Free Documentation License"

If you have no Invariant Sections, write "with no Invariant Sections instead of saying which ones are invariant. If you have n Front-Cover Texts, write "no Front-Cover Texts" instead o "Front-Cover Texts being LIST"; likewise for Back-Cover Texts

If your document contains nontrivial examples of program code, w recommend releasing these examples in parallel under your choice o free software license, such as the GNU General Public License to permit their use in free software

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