% fdl.tex % This file is a chapter.  It must be included in a larger document to work% properly.\chapter{GNU Free Documentation License}Version 1.1, March 2000\\ Copyright \copyright\ 2000  Free Software Foundation, Inc.\\     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA\\ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.\section*{Preamble}The purpose of this License is to make a manual, textbook, or otherwritten document ``free'' in the sense of freedom: to assure everyonethe effective freedom to copy and redistribute it, with or withoutmodifying it, either commercially or noncommercially.  Secondarily,this License preserves for the author and publisher a way to getcredit for their work, while not being considered responsible formodifications made by others.This License is a kind of ``copyleft'', which means that derivativeworks of the document must themselves be free in the same sense.  Itcomplements the GNU General Public License, which is a copyleftlicense designed for free software.We have designed this License in order to use it for manuals for freesoftware, because free software needs free documentation: a freeprogram should come with manuals providing the same freedoms that thesoftware does.  But this License is not limited to software manuals;it can be used for any textual work, regardless of subject matter orwhether it is published as a printed book.  We recommend this Licenseprincipally for works whose purpose is instruction or reference.\section{Applicability and Definitions}This License applies to any manual or other work that contains anotice placed by the copyright holder saying it can be distributedunder the terms of this License.  The ``Document'', below, refers to anysuch manual or work.  Any member of the public is a licensee, and isaddressed as ``you''.A ``Modified Version'' of the Document means any work containing theDocument or a portion of it, either copied verbatim, or withmodifications and/or translated into another language.A ``Secondary Section'' is a named appendix or a front-matter section ofthe Document that deals exclusively with the relationship of thepublishers or authors of the Document to the Document's overall subject(or to related matters) and contains nothing that could fall directlywithin that overall subject.  (For example, if the Document is in part atextbook of mathematics, a Secondary Section may not explain anymathematics.)  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For works informats which do not have any title page as such, ``Title Page'' meansthe text near the most prominent appearance of the work's title,preceding the beginning of the body of the text.\section{Verbatim Copying}You may copy and distribute the Document in any medium, eithercommercially or noncommercially, provided that this License, thecopyright notices, and the license notice saying this License appliesto the Document are reproduced in all copies, and that you add no otherconditions whatsoever to those of this License.  You may not usetechnical measures to obstruct or control the reading or furthercopying of the copies you make or distribute.  However, you may acceptcompensation in exchange for copies.  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In addition, you must do these things in the Modified Version:\begin{itemize}\item 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.\item 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 less than five).\item State on the Title page the name of the publisher of the   Modified Version, as the publisher.\item Preserve all the copyright notices of the Document.\item Add an appropriate copyright notice for your modifications   adjacent to the other copyright notices.\item 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.\item Preserve in that license notice the full lists of Invariant Sections   and required Cover Texts given in the Document's license notice.\item Include an unaltered copy of this License.\item Preserve the section entitled ``History'', and its title, and add to   it an item stating at least the title, year, new authors, and