TY  - BOOK
AU  - Cooper,Arthur
AU  - Dunbar,Carl O.
TI  - Permian fauna at el antimonio, western sonora, Mexico
T2  - Smithsonian Miscellaneous Colections ; 
PY  - 1953///
CY  - Washington, D. C : 
PB  - Smithsonian Institution, 
ER  -