00385nam a2200121Ia 4500008004100000041000800041082002300049100001300072245004000085300000800125952011500133999001500248211209s9999    xx            000 0 und d  aeng  a621.381 51 N75 BAL  aBALL A M  aRADIO VALVE AND SEMICONDUCTOR DATA   a180  00104070aRITbRITd2021-12-31l1o621.381 51 N75 BALp7520r2023-11-20 00:00:00s2023-11-20w2021-12-31yBK  c7520d7520