LaTeX: cite with [ ] argument in caption - arguments

Question

I need the source of images listed in the "list of figures".
To do this I want to cite inside the caption argument:
This works:
\caption[Plan,\protect\cite{damluji1992}]{Plan}
This works too but i need it in the caption argument like in the next example:
\cite[p.156]{damluji1992}
I need this which doesn't work:
\caption[Plan,\protect\cite[p.156]{damluji1992}]{Plan}
it gives me the error "Argument of \HAR#dcite has an extra }."
In the *.lof file the corresponding line looks like this:
\contentsline {figure}{\numberline {2}{\ignorespaces Plan, \cite [S.156}}{5}{figure.caption.4}
-> the cite argument in { } is missing!
Without the cite argument in [ ] it looks like this:
\contentsline {figure}{\numberline {2}{\ignorespaces Plan, \cite {damluji1992}}}{5}{figure.caption.4}

Answer 1

I stumbled on this page with the same question and then found the answer at http://www.latex-community.org/forum/viewtopic.php?f=50&t=6225
The solution: put curly braces around the cite command:
{\cite[Theorem~2]{mEtAl}}
The reason this is necessary is that you have an optional [] argument inside another optional [] argument.

Answer 2

In preamble:
\usepackage{caption}[2011/11/10]
\newcommand{\figsource}[1]{%
\addtocounter{figure}{-1}
\captionlistentry{source: #1}
}
in document:
\begin{figure}
\includegraphics...
\caption{whatever}
\figsource{whatever-source}
\end{figure}
produces:
List of Figures
1.1 whatever . . . . . . . . 29
1.1 whatever-source: . . . . 29