1. I. Barin, O. Knacke, Thermochemical Properties of Inorganic Substances, VolumeI, Supplement, Springer Verlag, Heidelberg (1973, 1977), pp.1-861.
2. H. E. Mc Gannon, The Making, Shaping and Treating of Steel, 9th edition,US Steel Company, Pittsburgh Pa. (1971) pp.297-298.