TY  - RPRT
TI  - High-resolution leaf-fossil record spanning the Cretaceous/ Tertiary boundary
AU  - Kirk R. Johnson
AU  - Douglas J. Nichols
AU  - M. Attrep
AU  - C. J. Orth
PY  - 1989
DO  - 10.1038/340708a0
UR  - https://pubs.usgs.gov/publication/70221499
ID  - 70221499
ER  -