00315nam a2200109Ia 4500008004100000082001500041100003000056245005800086250000900144260004300153300000900196240913s9999||||xx |||||||||||||| ||und|| a547 PAR/P aV S Parmar and H M Chawla 0aPrinciples of reaction mechanism in organic chemistry aNULL bSultan Chand and SonsaNew Delhic1978 a447p