Abstract:
Author's abstract of a dissertation for the degree of Doctor of Physicomathematical Sciences. The dissertation was defended on Nov. 10, 1977, at the session of the Specialized Council D 002.38.03 at the V. A. Steklov Mathematics Institute of the Academy of Sciences of the USSR. Official opponents: Corresponding Member of the Academy of Sciences of the USSR, Doctor of Physicomathematical Sciences, Professor A. G. Vitushkin; Corresponding Member of the Academy of Sciences of the USSR, Doctor of Physicomathematical Sciences, Professor V. K. Ivanov; Doctor of Physicomathematical Sciences, Professor Yu. F. Korobeinik.