TY  - BOOK
AU  - Wingard,G.Lynn
ED  - United States.
ED  - United States.
TI  - A detailed taxonomy of Upper Cretaceous and Lower Tertiary Crassatellidae in the eastern United States ; an example of the nature of extinction at the boundary
PY  - 1993///
CY  - Washington
PB  - U.S. Government Printing Office
ER  -