Harrington, Roger F.: 'Theory of loaded scatterers', Proceedings of the Institution of Electrical Engineers, 1964, 111, (4), p. 617-623, DOI: 10.1049/piee.1964.0111
IET Digital Library, https://digital-library.theiet.org/;jsessionid=2ug5gd3qc4ekd.x-iet-live-01content/journals/10.1049/piee.1964.0111