1. N. E. Paton and J. C. Williams, Hydrogen in Metals, Ed. by I. M. Bernstein and A. W. Thompson (American Society for Metals, Metals Park, Ohio, United States, 1974).
2. Hydrogen in Metals, Ed. by G. Alefeld and J. Volkl (Springer-Verlag, Heidelberg, 1978; Mir, Moscow, 1981), Vol. 1.
3. K. M. Mackay, Hydrogen Compounds of the Metallic Elements (E. and F. N. Spon, London, 1966).
4. V. L. Moruzzi, J. F. Janak, and A. R. Williams, Calculated Electronic Properties of Metals (Pergamon, New York, 1978).
5. O. Jepsen, Phys Rev. B: Solid State 1, 2988 (1975).