00262nam a22001097a 4500003000400000008004100004082001600045100001500061245002600076260004200102300000800144OSt231007b        |||||||| |||| 00| 0 eng d  a574.5bV98E  aVyas, A.B.  aEcological Principles  aMetropolitan, New DelhibI.S.P.c1975  a127