Gambling, W.A.; Matsumura, H.; Cowley, A.G.: 'Jointing loss in single-mode fibres', Electronics Letters, 1978, 14, (3), p. 54-55, DOI: 10.1049/el:19780039
IET Digital Library, https://digital-library.theiet.org/;jsessionid=mcevlq4nlvd8.x-iet-live-01content/journals/10.1049/el_19780039