Grebennikov, Andrei: 'Power amplifier design principles' (Materials, Circuits and Devices, 2019), 'Radio Frequency and Microwave Power Amplifiers. Volume 1: Principles, Device Modeling and Matching Networks', Chap. 1, pp. 1-72, DOI: 10.1049/PBCS071F_ch1
IET Digital Library, https://digital-library.theiet.org/;jsessionid=1hxkm3d8kbefl.x-iet-live-01content/books/10.1049/pbcs071f_ch1