00273nam a2200121Ia 4500100002500000490000600025654003000031245003000061260002700091082001300118300000800131546001200139  aRay-chaudhuri/ D.P.   v1  aElectricity and magnetism  aElectricity and magnetism  bChayanaCalcuttac1961  a530bRay  a184  aENGLISH