In article , AM
writes:

Can someone point me to a good explanation of this method ? I.e. by
analysing lensing effects in a galaxy cluster, it is possible to map
the distribution of DM within the cluster, and presumably also to
estimate the amount of DM present in the cluster.

Thanks,
AM

[Mod. note: there are many reviews of this topic that you can find
with a search engine or by searching ADS. For a recent one try
http://arxiv.org/abs/1303.3274 -- mjh]

Apart from Martin's suggestion, you might want to search for "weak
lensing", in order to filter out other gravitational-lens stuff which is
not related to what you are looking for. (In gravitational lensing,
"weak lensing" generally refers to (a) resolved (i.e. not point) sources
(b) which are not multiply imaged. So, usually, distorted and
magnified images of background galaxies as a result of the gravitational
field of the foreground lens (galaxy cluster).