Lancellotti, Vito: 'Advanced Theoretical and Numerical Electromagnetics. Volume 2: Field representations and the Method of Moments' (Electromagnetic Waves, 2021) DOI: 
IET Digital Library, https://digital-library.theiet.org/;jsessionid=1t17qdjrtr7j8.x-iet-live-01content/books/ew/sbew560g