1. Benson, T.M., and Buus, J.: Optical guiding in III–V semiconductor rib structures, (IEE Conf. Publ. 227 1983), p. 17–20
2. McIlroy, P.W.A.: ‘Spectral index method: single rib waveguide’, Robson, P.N., Kendall, P.C., Rib waveguide theory by the spectral index method, (Research Studies Press 1991),Chap. 5, p. 70–122