00581nam a2200181Ia 4500008004100000020001500041082001700056100001600073245004500089260005200134300000800186650001400194650002000208653002900228942001200257999001500269952011500284170901s1989    xx            000 0 und d  a8770891019  a333.72bS48P  aSingh, H.S. 0aPrinciples of Environmental Conservation  aDehradunbInternational Book Distributorsc1989  a273  aEconomics  aSocial sciences  aEnvironmental protection  2ddccBK  c2548d2548  00102ddc4070aRAUbRAUd2017-10-18eUBSPD, Patnag195.00l0o333.72 S48Pp42025r2017-10-18w1989-07-01yBK