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+\setheaders{Credits}
+\chapter*{Credits}
+%\addcontentsline{toc}{section}{Credits}
+
+\Coq{}~ is a proof assistant for higher-order logic, allowing the
+development of computer programs consistent with their formal
+specification. It is the result of about ten years of research of the
+Coq project. We shall briefly survey here three main aspects: the
+\emph{logical language} in which we write our axiomatizations and
+specifications, the \emph{proof assistant} which allows the development
+of verified mathematical proofs, and the \emph{program extractor} which
+synthesizes computer programs obeying their formal specifications,
+written as logical assertions in the language.
+
+The logical language used by {\Coq} is a variety of type theory,
+called the \emph{Calculus of Inductive Constructions}. Without going
+back to Leibniz and Boole, we can date the creation of what is now
+called mathematical logic to the work of Frege and Peano at the turn
+of the century. The discovery of antinomies in the free use of
+predicates or comprehension principles prompted Russell to restrict
+predicate calculus with a stratification of \emph{types}. This effort
+culminated with \emph{Principia Mathematica}, the first systematic
+attempt at a formal foundation of mathematics. A simplification of
+this system along the lines of simply typed $\lambda$-calculus
+occurred with Church's \emph{Simple Theory of Types}. The
+$\lambda$-calculus notation, originally used for expressing
+functionality, could also be used as an encoding of natural deduction
+proofs. This Curry-Howard isomorphism was used by N. de Bruijn in the
+\emph{Automath} project, the first full-scale attempt to develop and
+mechanically verify mathematical proofs. This effort culminated with
+Jutting's verification of Landau's \emph{Grundlagen} in the 1970's.
+Exploiting this Curry-Howard isomorphism, notable achievements in
+proof theory saw the emergence of two type-theoretic frameworks; the
+first one, Martin-L\"of's \emph{Intuitionistic Theory of Types},
+attempts a new foundation of mathematics on constructive principles.
+The second one, Girard's polymorphic $\lambda$-calculus $F_\omega$, is
+a very strong functional system in which we may represent higher-order
+logic proof structures. Combining both systems in a higher-order
+extension of the Automath languages, T. Coquand presented in 1985 the
+first version of the \emph{Calculus of Constructions}, CoC. This strong
+logical system allowed powerful axiomatizations, but direct inductive
+definitions were not possible, and inductive notions had to be defined
+indirectly through functional encodings, which introduced
+inefficiencies and awkwardness. The formalism was extended in 1989 by
+T. Coquand and C. Paulin with primitive inductive definitions, leading
+to the current \emph{Calculus of Inductive Constructions}. This
+extended formalism is not rigorously defined here. Rather, numerous
+concrete examples are discussed. We refer the interested reader to
+relevant research papers for more information about the formalism, its
+meta-theoretic properties, and semantics. However, it should not be
+necessary to understand this theoretical material in order to write
+specifications. It is possible to understand the Calculus of Inductive
+Constructions at a higher level, as a mixture of predicate calculus,
+inductive predicate definitions presented as typed PROLOG, and
+recursive function definitions close to the language ML.
+
+Automated theorem-proving was pioneered in the 1960's by Davis and
+Putnam in propositional calculus. A complete mechanization (in the
+sense of a semi-decision procedure) of classical first-order logic was
+proposed in 1965 by J.A. Robinson, with a single uniform inference
+rule called \emph{resolution}. Resolution relies on solving equations
+in free algebras (i.e. term structures), using the \emph{unification
+ algorithm}. Many refinements of resolution were studied in the
+1970's, but few convincing implementations were realized, except of
+course that PROLOG is in some sense issued from this effort. A less
+ambitious approach to proof development is computer-aided
+proof-checking. The most notable proof-checkers developed in the
+1970's were LCF, designed by R. Milner and his colleagues at U.
+Edinburgh, specialized in proving properties about denotational
+semantics recursion equations, and the Boyer and Moore theorem-prover,
+an automation of primitive recursion over inductive data types. While
+the Boyer-Moore theorem-prover attempted to synthesize proofs by a
+combination of automated methods, LCF constructed its proofs through
+the programming of \emph{tactics}, written in a high-level functional
+meta-language, ML.
+
+The salient feature which clearly distinguishes our proof assistant
+from say LCF or Boyer and Moore's, is its possibility to extract
+programs from the constructive contents of proofs. This computational
+interpretation of proof objects, in the tradition of Bishop's
+constructive mathematics, is based on a realizability interpretation,
+in the sense of Kleene, due to C. Paulin. The user must just mark his
+intention by separating in the logical statements the assertions
+stating the existence of a computational object from the logical
+assertions which specify its properties, but which may be considered
+as just comments in the corresponding program. Given this information,
+the system automatically extracts a functional term from a consistency
+proof of its specifications. This functional term may be in turn
+compiled into an actual computer program. This methodology of
+extracting programs from proofs is a revolutionary paradigm for
+software engineering. Program synthesis has long been a theme of
+research in artificial intelligence, pioneered by R. Waldinger. The
+Tablog system of Z. Manna and R. Waldinger allows the deductive
+synthesis of functional programs from proofs in tableau form of their
+specifications, written in a variety of first-order logic. Development
+of a systematic \emph{programming logic}, based on extensions of
+Martin-L\"of's type theory, was undertaken at Cornell U. by the Nuprl
+team, headed by R. Constable. The first actual program extractor, PX,
+was designed and implemented around 1985 by S. Hayashi from Kyoto
+University. It allows the extraction of a LISP program from a proof
+in a logical system inspired by the logical formalisms of S. Feferman.
+Interest in this methodology is growing in the theoretical computer
+science community. We can foresee the day when actual computer systems
+used in applications will contain certified modules, automatically
+generated from a consistency proof of their formal specifications. We
+are however still far from being able to use this methodology in a
+smooth interaction with the standard tools from software engineering,
+i.e. compilers, linkers, run-time systems taking advantage of special
+hardware, debuggers, and the like. We hope that {\Coq} can be of use
+to researchers interested in experimenting with this new methodology.
+
+A first implementation of CoC was started in 1984 by G. Huet and T.
+Coquand. Its implementation language was CAML, a functional
+programming language from the ML family designed at INRIA in
+Rocquencourt. The core of this system was a proof-checker for CoC seen
+as a typed $\lambda$-calculus, called the \emph{Constructive Engine}.
+This engine was operated through a high-level notation permitting the
+declaration of axioms and parameters, the definition of mathematical
+types and objects, and the explicit construction of proof objects
+encoded as $\lambda$-terms. A section mechanism, designed and
+implemented by G. Dowek, allowed hierarchical developments of
+mathematical theories. This high-level language was called the
+\emph{Mathematical Vernacular}. Furthermore, an interactive
+\emph{Theorem Prover} permitted the incremental construction of proof
+trees in a top-down manner, subgoaling recursively and backtracking
+from dead-alleys. The theorem prover executed tactics written in CAML,
+in the LCF fashion. A basic set of tactics was predefined, which the
+user could extend by his own specific tactics. This system (Version
+4.10) was released in 1989. Then, the system was extended to deal
+with the new calculus with inductive types by C. Paulin, with
+corresponding new tactics for proofs by induction. A new standard set
+of tactics was streamlined, and the vernacular extended for tactics
+execution. A package to compile programs extracted from proofs to
+actual computer programs in CAML or some other functional language was
+designed and implemented by B. Werner. A new user-interface, relying
+on a CAML-X interface by D. de Rauglaudre, was designed and
+implemented by A. Felty. It allowed operation of the theorem-prover
+through the manipulation of windows, menus, mouse-sensitive buttons,
+and other widgets. This system (Version 5.6) was released in 1991.
+
+\Coq{} was ported to the new implementation Caml-light of X. Leroy and
+D. Doligez by D. de Rauglaudre (Version 5.7) in 1992. A new version
+of \Coq{} was then coordinated by C. Murthy, with new tools designed
+by C. Parent to prove properties of ML programs (this methodology is
+dual to program extraction) and a new user-interaction loop. This
+system (Version 5.8) was released in May 1993. A Centaur interface
+\textsc{CTCoq} was then developed by Y. Bertot from the Croap project
+from INRIA-Sophia-Antipolis.
+
+In parallel, G. Dowek and H. Herbelin developed a new proof engine,
+allowing the general manipulation of existential variables
+consistently with dependent types in an experimental version of \Coq{}
+(V5.9).
+
+The version V5.10 of \Coq{} is based on a generic system for
+manipulating terms with binding operators due to Chet Murthy. A new
+proof engine allows the parallel development of partial proofs for
+independent subgoals. The structure of these proof trees is a mixed
+representation of derivation trees for the Calculus of Inductive
+Constructions with abstract syntax trees for the tactics scripts,
+allowing the navigation in a proof at various levels of details. The
+proof engine allows generic environment items managed in an
+object-oriented way. This new architecture, due to C. Murthy,
+supports several new facilities which make the system easier to extend
+and to scale up:
+
+\begin{itemize}
+\item User-programmable tactics are allowed
+\item It is possible to separately verify development modules, and to
+ load their compiled images without verifying them again - a quick
+ relocation process allows their fast loading
+\item A generic parsing scheme allows user-definable notations, with a
+ symmetric table-driven pretty-printer
+\item Syntactic definitions allow convenient abbreviations
+\item A limited facility of meta-variables allows the automatic
+ synthesis of certain type expressions, allowing generic notations
+ for e.g. equality, pairing, and existential quantification.
+\end{itemize}
+
+In the Fall of 1994, C. Paulin-Mohring replaced the structure of
+inductively defined types and families by a new structure, allowing
+the mutually recursive definitions. P. Manoury implemented a
+translation of recursive definitions into the primitive recursive
+style imposed by the internal recursion operators, in the style of the
+ProPre system. C. Mu{\~n}oz implemented a decision procedure for
+intuitionistic propositional logic, based on results of R. Dyckhoff.
+J.C. Filli{\^a}tre implemented a decision procedure for first-order
+logic without contraction, based on results of J. Ketonen and R.
+Weyhrauch. Finally C. Murthy implemented a library of inversion
+tactics, relieving the user from tedious definitions of ``inversion
+predicates''.
+
+\begin{flushright}
+Rocquencourt, Feb. 1st 1995\\
+Gérard Huet
+\end{flushright}
+
+\section*{Credits: addendum for version 6.1}
+%\addcontentsline{toc}{section}{Credits: addendum for version V6.1}
+
+The present version 6.1 of \Coq{} is based on the V5.10 architecture. It
+was ported to the new language Objective Caml by Bruno Barras. The
+underlying framework has slightly changed and allows more conversions
+between sorts.
+
+The new version provides powerful tools for easier developments.
+
+Cristina Cornes designed an extension of the \Coq{} syntax to allow
+definition of terms using a powerful pattern-matching analysis in the
+style of ML programs.
+
+Amokrane Saïbi wrote a mechanism to simulate
+inheritance between types families extending a proposal by Peter
+Aczel. He also developed a mechanism to automatically compute which
+arguments of a constant may be inferred by the system and consequently
+do not need to be explicitly written.
+
+Yann Coscoy designed a command which explains a proof term using
+natural language. Pierre Cr{\'e}gut built a new tactic which solves
+problems in quantifier-free Presburger Arithmetic. Both
+functionalities have been integrated to the \Coq{} system by Hugo
+Herbelin.
+
+Samuel Boutin designed a tactic for simplification of commutative
+rings using a canonical set of rewriting rules and equality modulo
+associativity and commutativity.
+
+Finally the organisation of the \Coq{} distribution has been supervised
+by Jean-Christophe Filliâtre with the help of Judicaël Courant
+and Bruno Barras.
+
+\begin{flushright}
+Lyon, Nov. 18th 1996\\
+Christine Paulin
+\end{flushright}
+
+\section*{Credits: addendum for version 6.2}
+%\addcontentsline{toc}{section}{Credits: addendum for version V6.2}
+
+In version 6.2 of \Coq{}, the parsing is done using camlp4, a
+preprocessor and pretty-printer for CAML designed by Daniel de
+Rauglaudre at INRIA. Daniel de Rauglaudre made the first adaptation
+of \Coq{} for camlp4, this work was continued by Bruno Barras who also
+changed the structure of \Coq{} abstract syntax trees and the primitives
+to manipulate them. The result of
+these changes is a faster parsing procedure with greatly improved
+syntax-error messages. The user-interface to introduce grammar or
+pretty-printing rules has also changed.
+
+Eduardo Giménez redesigned the internal
+tactic libraries, giving uniform names
+to Caml functions corresponding to \Coq{} tactic names.
+
+Bruno Barras wrote new more efficient reductions functions.
+
+Hugo Herbelin introduced more uniform notations in the \Coq{}
+specification language: the definitions by fixpoints and
+pattern-matching have a more readable syntax. Patrick Loiseleur
+introduced user-friendly notations for arithmetic expressions.
+
+New tactics were introduced: Eduardo Giménez improved a mechanism to
+introduce macros for tactics, and designed special tactics for
+(co)inductive definitions; Patrick Loiseleur designed a tactic to
+simplify polynomial expressions in an arbitrary commutative ring which
+generalizes the previous tactic implemented by Samuel Boutin.
+Jean-Christophe Filli\^atre introduced a tactic for refining a goal,
+using a proof term with holes as a proof scheme.
+
+David Delahaye designed the \textsf{SearchIsos} tool to search an
+object in the library given its type (up to isomorphism).
+
+Henri Laulhère produced the \Coq{} distribution for the Windows environment.
+
+Finally, Hugo Herbelin was the main coordinator of the \Coq{}
+documentation with principal contributions by Bruno Barras, David Delahaye,
+Jean-Christophe Filli\^atre, Eduardo
+Giménez, Hugo Herbelin and Patrick Loiseleur.
+
+\begin{flushright}
+Orsay, May 4th 1998\\
+Christine Paulin
+\end{flushright}
+
+\section*{Credits: addendum for version 6.3}
+The main changes in version V6.3 was the introduction of a few new tactics
+and the extension of the guard condition for fixpoint definitions.
+
+
+B. Barras extended the unification algorithm to complete partial terms
+and solved various tricky bugs related to universes.\\
+D. Delahaye developed the \texttt{AutoRewrite} tactic. He also designed the new
+behavior of \texttt{Intro} and provided the tacticals \texttt{First} and
+\texttt{Solve}.\\
+J.-C. Filli\^atre developed the \texttt{Correctness} tactic.\\
+E. Gim\'enez extended the guard condition in fixpoints.\\
+H. Herbelin designed the new syntax for definitions and extended the
+\texttt{Induction} tactic.\\
+P. Loiseleur developed the \texttt{Quote} tactic and
+the new design of the \texttt{Auto}
+tactic, he also introduced the index of
+errors in the documentation.\\
+C. Paulin wrote the \texttt{Focus} command and introduced
+the reduction functions in definitions, this last feature
+was proposed by J.-F. Monin from CNET Lannion.
+
+\begin{flushright}
+Orsay, Dec. 1999\\
+Christine Paulin
+\end{flushright}
+
+%\newpage
+
+\section*{Credits: versions 7}
+
+The version V7 is a new implementation started in September 1999 by
+Jean-Christophe Filliâtre. This is a major revision with respect to
+the internal architecture of the system. The \Coq{} version 7.0 was
+distributed in March 2001, version 7.1 in September 2001, version
+7.2 in January 2002, version 7.3 in May 2002 and version 7.4 in
+February 2003.
+
+Jean-Christophe Filliâtre designed the architecture of the new system, he
+introduced a new representation for environments and wrote a new kernel
+for type-checking terms. His approach was to use functional
+data-structures in order to get more sharing, to prepare the addition
+of modules and also to get closer to a certified kernel.
+
+Hugo Herbelin introduced a new structure of terms with local
+definitions. He introduced ``qualified'' names, wrote a new
+pattern-matching compilation algorithm and designed a more compact
+algorithm for checking the logical consistency of universes. He
+contributed to the simplification of {\Coq} internal structures and the
+optimisation of the system. He added basic tactics for forward
+reasoning and coercions in patterns.
+
+David Delahaye introduced a new language for tactics. General tactics
+using pattern-matching on goals and context can directly be written
+from the {\Coq} toplevel. He also provided primitives for the design
+of user-defined tactics in \textsc{Caml}.
+
+Micaela Mayero contributed the library on real numbers.
+Olivier Desmettre extended this library with axiomatic
+trigonometric functions, square, square roots, finite sums, Chasles
+property and basic plane geometry.
+
+Jean-Christophe Filliâtre and Pierre Letouzey redesigned a new
+extraction procedure from \Coq{} terms to \textsc{Caml} or
+\textsc{Haskell} programs. This new
+extraction procedure, unlike the one implemented in previous version
+of \Coq{} is able to handle all terms in the Calculus of Inductive
+Constructions, even involving universes and strong elimination. P.
+Letouzey adapted user contributions to extract ML programs when it was
+sensible.
+Jean-Christophe Filliâtre wrote \verb=coqdoc=, a documentation
+tool for {\Coq} libraries usable from version 7.2.
+
+Bruno Barras improved the reduction algorithms efficiency and
+the confidence level in the correctness of {\Coq} critical type-checking
+algorithm.
+
+Yves Bertot designed the \texttt{SearchPattern} and
+\texttt{SearchRewrite} tools and the support for the \textsc{pcoq} interface
+(\url{http://www-sop.inria.fr/lemme/pcoq/}).
+
+Micaela Mayero and David Delahaye introduced {\tt Field}, a decision tactic for commutative fields.
+
+Christine Paulin changed the elimination rules for empty and singleton
+propositional inductive types.
+
+Loïc Pottier developed {\tt Fourier}, a tactic solving linear inequalities on real numbers.
+
+Pierre Crégut developed a new version based on reflexion of the {\tt Omega}
+decision tactic.
+
+Claudio Sacerdoti Coen designed an XML output for the {\Coq}
+modules to be used in the Hypertextual Electronic Library of
+Mathematics (HELM cf \url{http://www.cs.unibo.it/helm}).
+
+A library for efficient representation of finite maps using binary trees
+contributed by Jean Goubault was integrated in the basic theories.
+
+Jacek Chrz\k{a}szcz designed and implemented the module system of
+{\Coq} whose foundations are in Judicaël Courant's PhD thesis.
+
+\bigskip
+
+The development was coordinated by C. Paulin.
+
+Many discussions within the Démons team and the LogiCal project
+influenced significantly the design of {\Coq} especially with
+%J. Chrz\k{a}szcz,
+J. Courant, P. Courtieu, J. Duprat, J. Goubault, A. Miquel,
+C. Marché, B. Monate and B. Werner.
+
+Intensive users suggested improvements of the system :
+Y. Bertot, L. Pottier, L. Théry , P. Zimmerman from INRIA,
+C. Alvarado, P. Crégut, J.-F. Monin from France Telecom R \& D.
+\begin{flushright}
+Orsay, May. 2002\\
+Hugo Herbelin \& Christine Paulin
+\end{flushright}
+
+\section*{Credits: version 8.0}
+
+{\Coq} version 8 is a major revision of the {\Coq} proof assistant.
+First, the underlying logic is slightly different. The so-called {\em
+impredicativity} of the sort {\tt Set} has been dropped. The main
+reason is that it is inconsistent with the principle of description
+which is quite a useful principle for formalizing %classical
+mathematics within classical logic. Moreover, even in an constructive
+setting, the impredicativity of {\tt Set} does not add so much in
+practice and is even subject of criticism from a large part of the
+intuitionistic mathematician community. Nevertheless, the
+impredicativity of {\tt Set} remains optional for users interested in
+investigating mathematical developments which rely on it.
+
+Secondly, the concrete syntax of terms has been completely
+revised. The main motivations were
+
+\begin{itemize}
+\item a more uniform, purified style: all constructions are now lowercase,
+ with a functional programming perfume (e.g. abstraction is now
+ written {\tt fun}), and more directly accessible to the novice
+ (e.g. dependent product is now written {\tt forall} and allows
+ omission of types). Also, parentheses and are no longer mandatory
+ for function application.
+\item extensibility: some standard notations (e.g. ``<'' and ``>'') were
+ incompatible with the previous syntax. Now all standard arithmetic
+ notations (=, +, *, /, <, <=, ... and more) are directly part of the
+ syntax.
+\end{itemize}
+
+Together with the revision of the concrete syntax, a new mechanism of
+{\em interpretation scopes} permits to reuse the same symbols
+(typically +, -, *, /, <, <=) in various mathematical theories without
+any ambiguities for {\Coq}, leading to a largely improved readability of
+{\Coq} scripts. New commands to easily add new symbols are also
+provided.
+
+Coming with the new syntax of terms, a slight reform of the tactic
+language and of the language of commands has been carried out. The
+purpose here is a better uniformity making the tactics and commands
+easier to use and to remember.
+
+Thirdly, a restructuration and uniformisation of the standard library
+of {\Coq} has been performed. There is now just one Leibniz' equality
+usable for all the different kinds of {\Coq} objects. Also, the set of
+real numbers now lies at the same level as the sets of natural and
+integer numbers. Finally, the names of the standard properties of
+numbers now follow a standard pattern and the symbolic
+notations for the standard definitions as well.
+
+The fourth point is the release of \CoqIDE{}, a new graphical
+gtk2-based interface fully integrated to {\Coq}. Close in style from
+the Proof General Emacs interface, it is faster and its integration
+with {\Coq} makes interactive developments more friendly. All
+mathematical Unicode symbols are usable within \CoqIDE{}.
+
+Finally, the module system of {\Coq} completes the picture of {\Coq}
+version 8.0. Though released with an experimental status in the previous
+version 7.4, it should be considered as a salient feature of the new
+version.
+
+Besides, {\Coq} comes with its load of novelties and improvements: new
+or improved tactics (including a new tactic for solving first-order
+statements), new management commands, extended libraries.
+
+\bigskip
+
+Bruno Barras and Hugo Herbelin have been the main contributors of the
+reflexion and the implementation of the new syntax. The smart
+automatic translator from old to new syntax released with {\Coq} is also
+their work with contributions by Olivier Desmettre.
+
+Hugo Herbelin is the main designer and implementor of the notion of
+interpretation scopes and of the commands for easily adding new notations.
+
+Hugo Herbelin is the main implementor of the restructuration of the
+standard library.
+
+Pierre Corbineau is the main designer and implementor of the new
+tactic for solving first-order statements in presence of inductive
+types. He is also the maintainer of the non-domain specific automation
+tactics.
+
+Benjamin Monate is the developer of the \CoqIDE{} graphical
+interface with contributions by Jean-Christophe Filliâtre, Pierre
+Letouzey, Claude Marché and Bruno Barras.
+
+Claude Marché coordinated the edition of the Reference Manual for
+ \Coq{} V8.0.
+
+Pierre Letouzey and Jacek Chrz\k{a}szcz respectively maintained the
+extraction tool and module system of {\Coq}.
+
+Jean-Christophe Filliâtre, Pierre Letouzey, Hugo Herbelin and
+contributors from Sophia-Antipolis and Nijmegen participated to the
+extension of the library.
+
+Julien Narboux built a NSIS-based automatic {\Coq} installation tool for
+the Windows platform.
+
+Hugo Herbelin and Christine Paulin coordinated the development which
+was under the responsability of Christine Paulin.
+
+\begin{flushright}
+Palaiseau \& Orsay, Apr. 2004\\
+Hugo Herbelin \& Christine Paulin\\
+(updated Apr. 2006)
+\end{flushright}
+
+\section*{Credits: version 8.1}
+
+{\Coq} version 8.1 adds various new functionalities.
+
+Benjamin Grégoire implemented an alternative algorithm to check the
+convertibility of terms in the {\Coq} type-checker. This alternative
+algorithm works by compilation to an efficient bytecode that is
+interpreted in an abstract machine similar to Xavier Leroy's ZINC
+machine. Convertibility is performed by comparing the normal
+forms. This alternative algorithm is specifically interesting for
+proofs by reflection. More generally, it is convenient in case of
+intensive computations.
+
+Christine Paulin implemented an extension of inductive types allowing
+recursively non uniform parameters. Hugo Herbelin implemented
+sort-polymorphism for inductive types.
+
+Claudio Sacerdoti Coen improved the tactics for rewriting on arbitrary
+compatible equivalence relations. He also generalized rewriting to
+arbitrary transition systems.
+
+Claudio Sacerdoti Coen added new features to the module system.
+
+Benjamin Grégoire, Assia Mahboubi and Bruno Barras developed a new
+more efficient and more general simplification algorithm on rings and
+semi-rings.
+
+Hugo Herbelin, Pierre Letouzey and Claudio Sacerdoti Coen added new
+tactic features.
+
+Hugo Herbelin implemented matching on disjunctive patterns.
+
+New mechanisms made easier the communication between {\Coq} and external
+provers. Nicolas Ayache and Jean-Christophe Filliâtre implemented
+connections with the provers {\sc cvcl}, {\sc Simplify} and {\sc
+zenon}. Hugo Herbelin implemented an experimental protocol for calling
+external tools from the tactic language.
+
+%Matthieu Sozeau developed an experimental language to reason over subtypes.
+
+A mechanism to automatically use some specific tactic to solve
+unresolved implicit has been implemented by Hugo Herbelin.
+
+Laurent Théry's contribution on strings and Pierre Letouzey and
+Jean-Christophe Filliâtre's contribution on finite maps have been
+integrated to the {\Coq} standard library. Pierre Letouzey developed a
+library about finite sets ``à la Objective Caml'' and extended the
+lists library.
+
+Pierre Corbineau extended his tactic for solving first-order
+statements. He wrote a reflexion-based intuitionistic tautology
+solver.
+
+Jean-Marc Notin took care of the general maintenance of the system.
+
+\begin{flushright}
+Palaiseau, Apr. 2006\\
+Hugo Herbelin
+\end{flushright}
+
+%\newpage
+
+% Integration of ZArith lemmas from Sophia and Nijmegen.
+
+
+% $Id: RefMan-pre.tex 8707 2006-04-13 18:23:35Z herbelin $
+
+%%% Local Variables:
+%%% mode: latex
+%%% TeX-master: "Reference-Manual"
+%%% End: