TY  - RPRT
TI  - Geochemical evidence for suppression of pelagic marine productivity at the Cretaceous/Tertiary boundary
AU  - James Zachos
AU  - M.A. Arthur
AU  - Walter E. Dean
PY  - 1989
DO  - 10.1038/337061a0
UR  - https://pubs.usgs.gov/publication/70210010
ID  - 70210010
ER  -