Ida, Nathan: 'Evaluation of the sensors' (Control, Robotics and Sensors, 2018), 'Open Resonator Microwave Sensor Systems for Industrial Gauging: A practical design approach', Chap. 6, pp. 233-261, DOI: 10.1049/PBCE103E_ch6
IET Digital Library, https://digital-library.theiet.org/;jsessionid=203huiphn3bh5.x-iet-live-01content/books/10.1049/pbce103e_ch6