000 00291nam a2200121Ia 4500
008 190711s9999 xx 000 0 und d
082 _a621.381512 S735
100 _aSPANGENBERG.K.R
245 0 _aVACUUM TUBES
260 _aNEW YORK
_bMcGraw-Hill
_c1948
300 _a22X15
942 _cBK
_2DDC
999 _c11044
_d11044