\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[latin1]{inputenc}
\usepackage{lmodern}
\usepackage{makeidx}
\usepackage[refpage]{nomencl}
\makeindex
\makeglossary
\title{package \texttt{nomencl}}
\author{Herbert Vo\ss}
\date{\today}

\begin{document}

\maketitle

\tableofcontents{}

\begin{abstract}
This is a nomencl-demo with the following preamble-commands\\
\begin{verbatim}
\usepackage[refpage]{nomencl}
\makeglossary
\end{verbatim}
For more information have a look at the nomencl-doc. The whole package
may be part of your local tex-installation or available at CTAN.
\end{abstract}

\section{Intro}
Very often a glossary or nomenclature is very useful for long or complex
texts. At first we'll have an equation
\begin{equation}
\dot{y}=y+c
\end{equation}

\nomenclature{$\dot{y}$}{The first abbreviation fo $y$ to the time $t$\refeq}
The $\dot{y}$ gets an entry in the nomenclature with 

\begin{verbatim}
\nomenclature{$\dot{y}$}{The first abbreviation fo $y$ to the time $t$\refeq}
\end{verbatim}

where the command \verb|\refeq| points to
the equation\nomenclature{equation}{Some kind of mathstuff} number
just before the \verb|nomenclature| command
(look at Nomenclature on page \pageref{glossar}). Same is possible
for refs to pages. In fact of the package option \verb|pageref|
every nomencl-entry gets a ref to the page where it is definied. Therefore
the entry for $\dot{y}$ has two refs.

text text text text text text with a nice formula $f(x)=x^{2+n}+1$
\nomenclature{$f(x)=x^{2+n}+1$}{a formula} 

text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text with the
European Community\nomenclature{EC}{European Community} 

text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text and another nice formula $f(x)=\int_{a}^{b}xdx$
\nomenclature{$f(x)=\int_{a}^{b}xdx$}{another formula with a long
text a formula ...} ext text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text


\section{Mathstuff}

One of the most important thing of the package nomenclature is that
there are no restrictions for the entries. Therefore you can write
any math expression.
The only thing that you have to remember is that these entries appear
in the sorted nomenclatur first. 

$f(x)=x$\nomenclature{$f(x)=x$}{a formula}

text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text 

\nomenclature{$f(x)=\sum_{i=a}^{b}x_{i}$}{a formula with a very
long text a formula with a very long text a formula with a very long
text a formula with a very long text a formula with a very long text
a formula with a very long text a formula with a very long text a
formula with a very long text a formula with a very long text a formula
with a very long text a formula with a very long text }

text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text like ASCII
\nomenclature{ASCII}{American Standard Code of Information Interchange} 

text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text text text text text text text text text text
text text text text text\index{text} text 

\addcontentsline{toc}{section}{\nomname}

\label{glossar}\printglossary

\printindex{}
\end{document}