1. A.C. Switendick, Topics in Applied Physics, Vol. 28: Hydrogen in Metals I: Basic. Properties, G. Alefeld and J. Völkl, Springer Verlag, Berlin 1978, p. 101.
2. A.C. Switendick, Zeits. Physik. Chem. Neue Folge, Bd. 117, S89 (1979).
3. D.A. Papaconstantopoulos, Proceedings of the NATO Advanced Study Institute on Metal Hydrides. (Plenum, 1981 ).
4. For recent theoretical discussions of the muffin-tin alloys see Refs. 5 to 9 below. A review up to 1975 is found in Section IX of H. Ehrenreich and L. Schwartz in Solid State Physics, edited by H. Ehrenreich, F. Seitz and D. Turnbull ( Academic, New York, 1976 ), Vol. 31.
5. A. Bansil, Phys. Rev. Letters 41, 1670 (1978); A. Bansil, Phys. Rev. B20, 4025 (1979); ibid, B20, 4035 (1979).