1. V. A. Anisimova, M. V. Levchenko, and Yu. V. Koshchenko, Inventor Certificate USSR, No. 952847: Otkrytiya, No. 31, 126 (1982).
2. V. A. Anisimova, M. V. Levchenko, and A. F. Pozharskii, Inventor Certificate USSR, No. 952848; Otrkrytiya, No. 31, 127 (1982).
3. V. A. Anisimova, M. V. Levchenko, Yu. V. Koshchenko, et al., Khim. Geterotsikl. Soedin., No. 3, 419 (1983).
4. O. E. Vatolkina and R. E. Libinzon, Khim.-farm. Zh., No. 2, 152–153 (1984).
5. V. G. Grigoryan and I. Z. Kiroshka, Lab. Delo, No. 7, 440–442 (1978).