00339nam a2200121Ia 4500008004100000040001700041082002200058100002200080245004000102260003600142300001100178650002800189190329s9999||||xx |||||||||||||| ||und||  aNITILcNITIL  221sta550.bP985M  aPuri, Kanchan Dr. 0aMain hoon PrathvicDr. Kanchan Puri  aDelhibDelhi Pustak Sadanc1999  a192pg,  aSCIENCE, EARTH SCIENCE,