1. Recent advances in power electronics
2. Evaluation of modern power semiconductor devices and future trends of converters
3. K. Spangenberg, Vacuum Tubes (McGraw-Hill, New York, NY, 1948) pp. 201–237.
4. E. Chaffee, Theory of Thermionic Vacuum Tubes (McGraw–Hill, New York, NY, 1933) pp. 144–191.
5. K. Spangenberg, Vacuum Tubes (McGraw–Hill, New York, NY, 1948) pp. 266–297.