\documentclass[11pt,a4paper]{article} 
% محمود امین‌طوسی، http://webpages.iust.ac.ir/mamintoosi
\usepackage{natbib}
\title{How to use Bib\TeX}
\author{Mahmood Amintoosi}\date{}
\begin{document}
\maketitle

How to use .bst files?
\begin{enumerate}
\item Your references should be in a .bib file, say 'SomeEnReferences.bib'
\item The above file and your .bst file should be in the system path or the current directory.
\item For seeing the file structure, see the source files of this example.
\item In TeXMaker, press F1, F11, F1 and F1.
\end{enumerate}

Example:
In \cite{Amintoosi09regional} a new method has been introduced.
\nocite{*}

\bibliographystyle{asa}
\bibliography{SomeEnReferences}


\end{document}