TY  - BOOK
AU  - Shrock, Robert R.
AU  - Twenhofel, William H.
TI  - Principles of invertebrate paleontology
SN  -  9788123912189
U1  - 560 
PY  - 1987///, r2005
CY  - Kolkata
PB  - CBS
KW  - PALEONTOLOGY
ER  -