this website exists no more:
http://www.biology.ucsc.edu/classes/bio161l/NUDI/fcooperi.html
http://slugsite.us/bow/nudwk203.htm
http://slugsite.us/bow/flab99_1.htm
http://www.medslugs.de/E/Pac-NE/Orienthella_cooperi/Selection.htm
http://www.nudipixel.net/species/flabellina_cooperi/
http://slugsite.us/bow2007/nudwk797.htm