1. S. V. Shorshnev and S. E. Esipov, Khim. Geterotsikl. Soedin., No. 2, 274 (1989).
2. A. F. Pozharskii, V. V. Kuz'menko, A. V. Gulevskaya, S. V. Shorshnev, S. E. Esipov, and A. I. Chernyshev, ?New methods and reagents in fine organic synthesis,? in: Abstracts of Reports, 5th All-Union Symposium on Organic Synthesis, Nauka, Moscow (1988), p. 7.
3. S. V. Shorshnev, S. E. Esipov, A. I. Chernyshev, A. F. Pozharskii, V. V. Kuz'menko, and A. V. Gulevskaya, Khim. Geterotsikl. Soedin., No. 2, 224 (1990).
4. G. G. Aleksandrov and S. E. Esipov, Antibiot. Med. Biotekhnol., No. 3, 181 (1986).
5. J. Shmushkevich, Advances in Organic Chemistry [in Russian], Mir, Moscow (1966), Vol. 4, p. 5.