TY  - BOOK
AU  - SHROCK,  ROBERT.R
AU  - TWENHOFEL, WILLIAM .H
TI  - PRINCIPLES OF INVERTEBRATE PALEONTOLOGY
U1  - 562 
PY  - 2002///
CY  - New Delhi
PB  - C.B.S. Publishers and Distrbutors, New Delhi 
ER  -