1. I. N. Grantsevich, Poroshkovaya Met., No. 2, 9 (1962).
2. S. G. Tresvyatskii, Poroshkovaya Met., No. 4, 63 (1968).
3. D. M. Darpinos and L. I. Tuchinskii, Poroshkovaya Met., No. 9, 85 (1968).
4. N. N. Dergunov and V. N. Barabanov, in: Graphite Base Constructional Materials [in Russian], Vol. 4 (1969), p. 97.
5. S. Mrozowski, First and Second Conferences on Carbon, Buffalo (1955), p. 31.