Cope, E.D. (1869)
Second addition to the history of the fishes of the Cretaceous of United states. Proceedings of the American Philosophical Society, 11(81), 240–244
Cope, E.D. (1875)
The Vertebrata of the Cretaceous formations of the West. Report of the United States Geological Survey of the Territories, 2: 303 p., 67 pl.