TY  - BOOK
AU  - SHROCK, ROBERT R
AU  - TWENHOFEL, WILLIAM H
TI  - Principles of Invertebrate Paleontology
U1  - H6(K1) 
PY  - 1953///
CY  - DELHI
PB  - CBS PUBLISHERS & DISTRIBUTORS
KW  -  PRINCIPLES OF INVERTEBRATE PALEONTOLOGY
KW  - MEDICAL
ER  -