\chapter*{Preface}\markboth{Preface}{Preface}

This volume provides documentation for the user-contributed libraries
distributed with the \HOL\ system.  It should be read in conjunction with the
\HOL\ system documentation, which consists of three volumes:

\begin{myenumerate}
\item \TUTORIAL: a tutorial introduction to \HOL, with case studies.
\item \DESCRIPTION: a description of higher order logic,
the \ML\ programming language, and theorem proving methods in the \HOL\ system;
\item \REFERENCE: the reference documentation of the tools available in \HOL.
\end{myenumerate}

\noindent These documents are be referred to by the short names (in small
slanted capitals) given above.

The present volume, \LIBRARIES, contains a collection independent sections, one
for each documented library distributed with the system. This documentation,
which is written by the contributors of the corresponding \HOL\ system
libraries, is not, strictly speaking, part of the \HOL\ manual set, which
consists of the three volumes listed above.  The \LIBRARIES\ documentation is,
however, typeset and distributed with the system in a form consistent with the
\HOL\ system documentation.


