Palynology and microstratigraphy of Cretaceous-Tertiary boundary sections in southwestern North DakotaDOI: info:10.1130/0-8137-2361-2.95v. 361Geological Society of America95–143
Nichols, Douglas J. and Johnson, Kirk R. 2002. "Palynology and microstratigraphy of Cretaceous-Tertiary boundary sections in southwestern North Dakota." In The Hell Creek Formation and the Cretaceous-Tertiary boundary in the northern Great Plains: An Integrated continental record of the end of the Cretaceous ; Special Paper 361. Hartman, Joseph H., Johnson, Kirk R., and Nichols, Douglas J., editors. 95–143. Geological Society of America. 361 https://doi.org/10.1130/0-8137-2361-2.95.