http://www.seaslugforum.net/showall/madrferr
http://www.umiushi.info/photo_species/photo_splist_eng.php?sopt=0&loc=0000
http://www.ne.jp/asahi/kappa-kuri/miyamoto/OSEHOO/umiushi117.html
http://www.koretz.net/Eilat/Invertebrates/Molluscs/Nudibranchs/Mferruginosa.htm
http://www.medslugs.de/E/Pac-NW/Madrella_ferruginosa/Selection.htm
http://www.underwaterkwaj.com/nudi/arminaceans/e415.htm
http://www.medslugs.de/E/Ind-NW/Madrella_ferruginosa/Selection.htm
http://www.nudipixel.net/species/madrella_ferruginosa/
http://www.umiushi-zukan.com/eng/list_pic.php?ssw=g&kind_id=420
http://www.nuditahiti.com/liste-des-espèces/madrella-ferruginosa/
https://www.Philippine-Sea-Slugs.com/Nudibranchia/Cladobranchia/Madrella_ferruginosa.htm
http://slugsite.us/bow2007/nudwk1002.htm
https://www.vibrantsea.net/madrella8553_anilao2019.htm