LaTeX acronym package

From CTAN:

This package ensures that all acronyms used in the text are spelled out in full at least once. It also provides an environment to build a list of acronyms used.

The basic usage is described below:

\usepackage[printonlyused, withpage]{acronym}

If you don’t want to print the list of acronyms:

\usepackage[nolist]{acronym}

The options ensure that only used acronyms are printed out and that the page number of the first reference to the acronym is displayed.

In the text, when you want to use an acronym (here SOM) use this command:

\ac{SOM}

At the place you want to list the acronyms add this environment:

\begin{acronym}
\acro{SOM}{Self-Organizing Map}
\end{acronym}