1. Amplification of small alternating tensions by an inductive action of the electrons in a radio valve with negative anode;Bakker;Physica,1934
2. On vacuum tube electronics;Bakker;Physica,1935
3. “Velocity Modulated Thermionic Tubes.”;Beck,1948
4. Reflex klystrons for centimetre links;Beck;Proc. Inst. Elec. Engrs. (London) Pt. III A,1952
5. Current and power in velocity-modulation tubes;Black;Proc. Inst. Radio Engrs.,1944