World Register of Marine Species (WoRMS)
MolluscaBase eds. (2026). MolluscaBase. Helicocranchia pfefferi Massy, 1907. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=139424 on 2026-08-29
Massy, A.L. (1907). Preliminary notice of new and remarkable cephalopods from the south-west coast of Ireland. Annals and Magazine of Natural History. 20(7): 377-384.
Robson, G. C. (1948). The Cephalopoda Decapoda of the "Arcturus" Oceanographic Expedition. Zoologica. 33(3): 115-132, 18 figs.