Tube Lore (II) p. 77
Babani, International Radio Tube Encyclopaedia p. 182 & 183
Universal Vade-Mecum, Electron Valves and Semiconductor Devices
Taschenbuch zum Röhren-Codex 1948/49
830B: ARRL Handbook 1972
Anonimo 10 Collezionista
Just Qvigstad
830B: RCA Technical Manual TT3
Miguel Angel Trujillo-Rodriguez
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