1. J. N. Kuznia, M. A. Khan, D. T. Olson, and R. Kaplan, J. Appl. Phys. 73, 4700 (1993).
2. V. N. Danilin, T. A. Zhukova, Yu. Kuznetsov, et al., Elektronika, No. 4, 20 (2005).
3. L. Borisov and G. Shchelkunov, Elektronika, No. 4, 102 (2012).
4. G. Formicone, F. Boueri, and B. Battaglia, in Proceedings of the IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems COMCAS, Tel Aviv, Israel, October 21–23, 2013, p. 4.
5. A. Grebennicov, Switchmode RF and Microwave Power Amplifier (Academic, New York, 2012), p. 345.