1. AstroArts Novae and Supernovae Observable Novae, and Supernovae. Plus a database of all current novae, and supernovae. Includes finding charts for bright objects. http://www.astroarts.com/
2. MOST Supernova Remnant Catalogue SNR catalogs and images from the University of Sydney. http://www.physics.usyd.edu.au/astrop/wg96cat/
3. SAI Supernova Catalog Sternberg Astronomical Institute - Moscow, Russia. http://www.sai.msu.su/cgi-bin/wdb-p95/sn/sncat/form