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standard Abelian category

\documentclass{article}
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\begin{document}
The following is an alternative definition of an \emph{Abelian category} (according to Barry Mitchell's textbook):

\begin{definition}
An \emph{Abelian category} is an \PMlinkname{exact}{CategoricalSequence} 
additive category with finite products. 
\end{definition}

The following theorem from ref.\cite{BM65} is also relevant as it relates key properties of Abelian categories:
\begin{quote}
``The following statements are equivalent:
\begin{enumerate}
\item \textbf{$\A$} is an Abelian category; 
\item \textbf{$\A$} has kernels, cokernels, finite products, finite coproducts,
 and is both normal and comormal; 
\item \textbf{$\A$} has pushouts and pullbacks and is both normal and conormal''.
\end{enumerate}
\end{quote}


\begin{thebibliography}{9}
\bibitem{BM65}
Barry Mitchell. \emph{Theory of Categories}, Academic Press: New York and London, 1965,  
(\textbf{Theorem 20.1} on p.33). 
\end{thebibliography}

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