ISI Web of Science, part of the ISI Web of Knowledge can be used to find references that cite a particular author or journal article.

A short tutorial on the Web of Science is available.  It is provided by ISI.
Please note that the University Libraries does not subscribe to either Index Chemicus or Current Chemical Reactions.

To access this short tutorial: http://scientific.thomson.com/tutorials/wos7/wos7tut1.html