1. N.N. Greenwood and A. Earnshaw, The Chemistry of the Elements, p. 1291, Pergamon Press, Oxford (1984).
2. I. Barin, Thermochemical Data of Pure Substances, 3rd edition, Vol. II, VCH, Weinheim (1995).
3. O. Knacke, O. Kubaschewski, and K. Hesselmann, eds., Thermochemical Properties of Inorganic Substances II., 2nd edition, Springer-Verlag, Heidelberg (1991).
4. S.W.H. Yih and C.T. Wang, Tungsten, Plenum Press, New York (1979).
5. Gmelin Handbook of Inorganic Chemistry, 8th ed., Syst. No. 54, Tungsten, Suppl. Vol. A6a, Springer-Verlag, Heidelberg (1991).