Boston University Open Cluster Database - This database contains characteristic properties of the known open star clusters. For most clusters, a corresponding FITS image file can be downloaded. astro.bu.edu/ocl
Catalogue of Open Cluster Data (5th Ed.) - A computer readable catalogue of open cluster data compiled by Gosta Lynga, Lund Observatory cdsweb.u-strasbg.fr/cgi-bin/Cat?VII/92A
WEBDA - A site devoted to open star clusters. It is mainly intended for professional and amateur astronomers obswww.unige.ch/webda
