Morrison, J.P.E. 1946. The nonmarine mollusks of San Jóse Island, with notes on those of Pedro González Island, Pearl Islands, Panamá. Smithsonian Miscellaneous Collections 106(6). 49 pp. Available electronically.
Morrison, 1946. Smithsonian Misc. Coll. 106(6): 46, pl. 1, figs. 4, 7.
Morrison, 1946. Smithsonian Misc. Coll. 106(6): 45, pl. 1, figs. 8-11.
Morrison, 1946. Smithsonian Misc. Coll. 106(6): 44, pl. 1, figs. 12-14.