TY  - RPRT
TI  - Preservation of cycad and Ginkgo pollen
AU  - N. O. Frederiksen
PY  - 1978
DO  - 10.1016/0034-6667(78)90036-2
UR  - https://pubs.usgs.gov/publication/70010378
ID  - 70010378
ER  -