Lu, Yun-Long; Wang, Yi; Hua, Changzhou; Liu, Taijun: 'Wide stopband out-of-phase filtering power divider using double-sided parallel-strip line', Electronics Letters, 2017, 53, (25), p. 1659-1661, DOI: 10.1049/el.2017.3677
IET Digital Library, https://digital-library.theiet.org/;jsessionid=2196l4imxhukl.x-iet-live-01content/journals/10.1049/el.2017.3677