1. M. Erola, J. Keinonen, A. Anttila and J. Koskinen. Solar Energy Mater., 12, 353 (1986).
2. C. Ernsberger, A. Miller and D. Banks. J. Vac. Sci. Technol. A, 3, 2303 (1985).
3. I. Suni, M. Mäenpää, M.A. Nicole and M. Luomajärvi. J. Electrochem. Soc., 130, 1215 (1983).
4. M. Wittmer. J. Vac. Sci. Technol. A, 3, 1797 (1985).
5. R. Freer (Ed.) The Physics and Chemistry of Carbides, Nitrides and Borides, (Kluwer, Dordrecht, 1990).