Maury, C.J. 1902. A comparison of the Oligocene of Western Europe and the southern United States. Bulletins of American Paleontology 3(15): 311-428. Available electronically.
Maury, 1902. Bull. Amer. Paleont. 3(15): 389 [79], pl. 29, figs. 3, 5-7.
Maury, 1902. Bull. Amer. Paleont. 3(15): 389 [79], pl. 29, fig. 4.
Maury, 1902. Bull. Amer. Paleont. 3(15): 388 [78], pl. 29, figs. 1-2.