1. V. I. Votyakov, B. F. Semenov, and V. M. Zhdanov, Prospects for the Scientific Development of Antiviral Drugs [in Russian], Minsk (1978), pp. 3–13.
2. V. I. Votyakov, Problems and Prospects for the Study of Nucleosides, Bicycloheptane, Adamantane, and Other Antiviral Compounds [in Russian], Minsk (1982), pp. 3–16.
3. D. E. Gilbert, Sulfonation of Organic Compounds [in Russian], Moscow (1969).
4. V. I. Il'enko, Methods of Testing and Evaluation of Antiviral Activity of Chemical Compounds against Influenza Virus [in Russian], Leningrad (1977), pp. 12–15.
5. N. K. Jerne and A. A. Nordin, Science,140, 405 (1963).