00370nam a2200133Ia 4500008004000000020001800040082001500058100001600073245004800089260003400137300001200171650003400183700001900217210210b1999   xxu||||| |||| 00| 0 eng d  a81 219 1681 X  a574.5 VERC  aVERMA (P S)  aConcepts of ecology: environmental biology.  aNDbS. Chand & Co. Ltd.c1999  avii,264  aEcology environmental biology  aAGARWAL (V K).