original description
Meek, F.B.; Hayden, F.V. (1856). Descriptions of New Species of Acephala and Gastropoda, from the Tertiary formations of Nebraska Territory, with some general remarks on the Geology of the country about the sources of the Missouri River. <em>Proceedings of the Academy of Natural Sciences of Philadelphia.</em> 8: 111-126., available online at https://www.biodiversitylibrary.org/page/1935165
page(s): 119 [details]
additional source
Russell, L.S. (1964). Cretaceous Non-marine Faunas of Northwestern North America. <em>Royal Ontario Museum and University of Toronto, Life Sciences, Contributions.</em> 61: 1-24., available online at https://www.biodiversitylibrary.org/page/36250220
page(s): 17 [details] Available for editors [request]
additional source
Cockerell, T. D. A. (1905). <i>Physa rhomboidea</i>. <em>The Nautilus.</em> 19(8): 96., available online at https://www.biodiversitylibrary.org/page/1755669 [details]
From editor or global species database
Type locality Buford ("Three miles above Fort Union"), North Dakota, United States; Fort Union Formation, Paleocene [details]