C. J.  Zagal and Hermosilla, C., Guide to Marine Invertebrates of Valdivia. Santiago: Quebecor World Chile, S.A, 2001, p. 217.

C. J.  Zagal and Hermosilla, C., Guide to Marine Invertebrates of Southern Chile. Punta Arenas: Fantastico Sur Birding Ltda., 2007, p. 263.