00342    a2200097   4500082002000000100003700020245009500057260005700152300001500209650002000224  a621.381537bOPE  aThe open university of Sri Lanka  aThe degree of bachelor of science blevel fourbphysics, electronics b supplementary book  aNawalabThe open university of Sri Lankac1986g1986  a73p.c28cm  aApplied physics