000 00293nam a2200121Ia 4500
008 210901s1920 xx 000 0 eng d
082 _a537.5 ALF
100 _aAlfrey, G.F.
245 0 _aPhysical electronics
260 _aLondon
_bD,.Van Norstrand
_c1920
650 _aPhysics
942 _2ddc
_cBK
999 _c2603
_d2603