TY  - RPRT
TI  - Vertebrate biostratigraphy of the Hell Creek Formation in southwestern North Dakota and northwestern South Dakota
AU  - Dean Pearson
AU  - Terry Schaeffer
AU  - Kirk R. Johnson
AU  - Douglas J. Nichols
AU  - John P. Hunter
PY  - 2002
DO  - 10.1130/0-8137-2361-2.145
UR  - https://pubs.usgs.gov/publication/70221502
ID  - 70221502
ER  -