TY  - BOOK
AU  - Twenhofel,William H.
AU  - Shrock,Robert Rakes
TI  - Principles of invertebrate paleontology
PY  - 1953///
CY  - New York
PB  - McGraw-Hill
KW  - Invertebrates, Fossil
N1  - 'A revised and enlarged edition of Twenhofel and Shrock, Invertebrate paleontology.'
ER  -