Della Valle, G.; Taccheo, S.; Laporta, P.; Sorbello, G.; Cianci, E.; Foglietti, V.: 'Compact high gain erbium-ytterbium doped waveguide amplifier fabricated by Ag-Na ion exchange', Electronics Letters, 2006, 42, (11), p. 632-633, DOI: 10.1049/el:20060555
IET Digital Library, https://digital-library.theiet.org/;jsessionid=1mju6x4ge23in.x-iet-live-01content/journals/10.1049/el_20060555