Johnson, N.P.; Khokhar, A.Z.; Chong, H.M.H.; De La Rue, R.M.; McMeekin, S.: 'Characterisation at infrared wavelengths of metamaterials formed by thin-film metallic split-ring resonator arrays on silicon', Electronics Letters, 2006, 42, (19), p. 1117-1119, DOI: 10.1049/el:20062212
IET Digital Library, https://digital-library.theiet.org/;jsessionid=12v9cugk2awjo.x-iet-live-01content/journals/10.1049/el_20062212