1. S. S. Belyaeva, L. L. Zaiygin, T. V. Frolova, et al., in: Improvement of Technical-Grade Carbon Production [in Russian], TsNIITEneftekhim, Moscow (1979), pp. 131?137.
2. R. A. Burdett, L. W. Taylor, and L. G. Jones, Molecular Spectroscopy, Institute of Petroleum, London (1955), pp. 30?32.
3. A. G. Siryuk and K. I. Zamina, Organic Analysis [in Russian], Vol. 13, Izd. Akad. Nauk SSSR, Moscow (1963), pp. 359?365.
4. I. H. Brown and W. R. Ladner, Fuel,39, No. 1, 87?96 (1960).
5. D. A. Rozental', I. A. Posadov, O. G. Popov, et al., Methods for Determining and Calculating Structural Parameters of Heavy Crude Residue Fractions [in Russian], LTI Lensoveta, Leningrad (1981).