000 00352cam a22001217a 4500
008 180718b1989 xxu||||| |||| 00| 0 eng d
082 _aY Si64
100 _aSingh, H.S.
245 _aPrinciples of environmental conservation
_cby H.S. Singh
260 _aDehradun
_bInternational Book Distributors
_c1989
300 _a273p.
650 _aNatural resources
999 _c353188
_d353188