1. M. V. Pridantsev and K. A. Lanskaya, Steels for Boilermaking [in Russian], Metallurgizdat, Moscow (1959).
2. D. Lavelles and F. Bloom, Iron Age, 179, No. 25 (1957).
3. M. P. Sidel'kovskii et al., Stal', No. 3 (1966).
4. M. P. Sidel'kovskii et al., in: Rare Earth Metals and Alloys [in Russian], No. 2, Kiev-Odessa (1968).
5. E. Simons, Boron in Steel Tooling, 14, No. 3 (1960).