Possible Duplicate:
length between nested lists
Possible duplicate:
In order to better distinguish groups of notions, I'd like to be able to control the vertical space between items of itemize when subitems are also used as follows:
\begin{itemize}
\item level 1 a
\begin{itemize}
\item level 2 a
\item level 2 b
\end{itemize}\vspace*{2mm}
\item level 1 b
\end{itemize}
How to automatically set-up a 2mm vertical space when subitems are used and nothing otherwise?
