00305nam a2200133Ia 4500008004100000020001800041082000800059082001000067100001700077245001100094260001400105260004300119260000900162230118s9999||||xx |||||||||||||| ||und||  a0-07-460138-5  a535  bGHA/O  aajoybghatak 0aoptics  anew delhi  btata mcgrawhill publishing company ltd  c1992