http://slugsite.us/bow/nudwk215.htm
http://slugsite.us/bow/shell_va.htm
http://www.vibrantsea.net/aplysia12_channel3.html
http://www.seaslugforum.net/showall/aplyvacc
http://scottpenny.smugmug.com/gallery/3881249_R9eMK
http://www.medslugs.de/E/Pac-NE/Aplysia_vaccaria/Selection.htm