Ryakhovskaya, M. I.; Popova, E. V.; Andryushina, V. A.; Grinenko, G. S. Pharmaceutical Chemistry Journal, 1990 , vol. 24, # 11 p. 839 - 842 Khimiko-Farmatsevticheskii Zhurnal, 1990 , vol. 24, # 11 p. 55 - 57