Cutler, Edward B. & Cutler, Norma J (1989): A revision of the genus Aspidosiphon (Sipuncula: Aspidosiphonidaea). Proceedings of Biological Society of Washington 102(4):826-865 [http://biostor.org/reference/65734.text Bistor
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Cutler, Edward B. (1994): The Sipuncula: their systematic, biology and evolution. 406p ISBN 0-8014-2843-2Google Book