http://www.habitas.org.uk/marinelife/species.asp?item=W13380
http://www.seaslugforum.net/factsheet/onchspar
http://opistobranquis.info/en/guia/nudibranchia/euctenidiacea/doridacea/onchidoris-sparsa/
http://www.medslugs.de/E/Med/Knoutsodonta_sparsa/Selection.htm