Descrição original: Olsson, A. A. (1922). The Miocene of northern Costa Rica with notes on its general stratigraphic relations. Bulletins of American Paleontology. 9(39): 173-481 [1-309], pls 1-32 [4-35]., available online at https://www.biodiversitylibrary.org/page/46040597 page(s): 227