TY  - RPRT
TI  - Plant microfossil record of the terminal cretaceous event in the western United States and Canada
AU  - Douglas J. Nichols
AU  - R. Farley Fleming
PY  - 1990
DO  - 10.1130/spe247-p445
UR  - https://pubs.usgs.gov/publication/70221504
ID  - 70221504
ER  -