1. R. L. JEPSEN, Enhanced emission, in Vol. I, Section 4.9.
2. Enhanced emission from magnetron cathodes;JEPSEN;J. Appl. Phys.,1951
3. Ionic bombardment heating of magnetron cathodes;BARRINGTON;Brit. J. Appl. Phys.,1955
4. “Electronic and Ionic Impact Phenomena.”;MASSEY,1952