TY  - BOOK
AU  - Ehlers, Ernest G.  .
TI  - Petrology igneous, sedimentary and metamorphic / 
SN  - 81-239-1032-0
U1  - H2 
PY  - 1999///
CY  - Delhi : 
PB  - CBS Publishers & Dishtributors , 
KW  - Petrology
ER  -