1. V. V. Ershov, G. A. Zlobina, and G. A. Nikiforov, Izv. Akad. Nauk SSSR, Ser. Khim., 1877 (1963).
2. G. A. Zlobina and V. V. Ershov, Izv. Akad. Nauk SSSR, Ser. Khim., 1675 (1965);
3. V. V. Ershov and G. A. Zlobina, Izv. Akad. Nauk SSSR, Ser. Khim., 2082 (1964).
4. V. V. Ershov and A. A. Volod'kin, Izv. AN SSSR, Otd. khim. n., 730 (1962);
5. A. A. Volod'kin and V. V. Ershov, ibid., 2022 (1962).