00265nam a2200109Ia 4500020001800000082001700018100001700035245002500052260003800077650002500115700001500140  a9788121914697  a530.15 DAS/M  aDass, H. K.  0aMathematical Physics  bS. Chand & Co. aNew Delhi c2010  aMathematical Physics  aRama Verma