1. 1A. E. Karbowiak, and Leo Young ; pp.75 -113 inAdvances in Microwaves , Vol. 1 . Academic Press, New YorkandLondon, 1966 .
2. Cylindrical Dielectric Waveguide Modes*
3. Dielectric-fibre surface waveguides for optical frequencies
4. 5I. Kitano, K. Koizumi, and H. Matsumura , "Light-Conducting Glass Structure and Production Thereof," Japanese Pat. Appl. March 15, 1968 ; German Pat. 1913358; Belgian Pat. 729880.