original descriptionIkeda, I. (1908). Note on a new deep-sea echiuroid, Protobonellia Mitsukurii. <em>Annotationes Zoologicae Japonenses.</em> 6(4): 259–265., available online athttps://www.biodiversitylibrary.org/page/44258445 page(s): 259. [details]
additional sourceMurina, Vantsetti. List of Echiura.[details]
additional sourceSatô, H. (1939). Studies on the Echiuroidea, Sipunculoidea and Priapuloidea of Japan. <em>Science Reports of the Tôhoku Imperial University, Fourth Series, Biology.</em> 14 (4): 339–460, plates XIX–XXIII.[details]