Yao, Xianxun; Sun, Guolin: 'Wideband horn antenna based on multi-substrate layer technology', Electronics Letters, 2019, 55, (1), p. 5-6, DOI: 10.1049/el.2018.6399 IET Digital Library, https://digital-library.theiet.org/;jsessionid=1dfgx377rsxk3.x-iet-live-01content/journals/10.1049/el.2018.6399