Reference tracking for OSX

    How do you keep track of all those references, excerpts and
links? Reference Tracker is an indispensable tool for writers,
researchers or students. It creates documents that store all
the citations and references in an essay, research project,
or book and automatically creates formatted reference
lists in a variety of popular reference styles
to insert when needed.

http://www.ugnn.com/2009/11/reference-tracking-for-osx/