Donald started following the work of John P. Hart, New York State Museum, Research & Collections Division. 2012-03-11 17:23:21 -0700

Donald started following the work of Hank Blumenthal, Georgia Institute of Technology, Digital Media in Literature, Communication, and Culture. 2011-10-12 07:22:26 -0700

Donald followed the paper: The stones of the Svevian castle of Rocca Imperiale (Calabria, southern Italy): characterization and provenance by Domenico Miriello 2011-10-02 12:27:03 -0700