M. P. A.  Traustedt, ?Kara Havets Spunge (Ascidiae Simplices).?, Dijmphna Togtets Zoologische -Bot. Udbytte, pp. 419-437, 1886.

W. A.  Herdman, ?Report on the Tunicata collected during the years 1873-1876, Part 2: Ascidiae Compositae?, Zoological Report on the Challenger Expedition, vol. 14, pp. 1-429, 1886.