1. A. V. Arkhangel'skii and D. B. Shakhmatov, ?Splitting spaces and questions of the approximation of functions,? Fifth Tiraspol Symposium on General Topology and Its Applications [in Russian], Shtiintsa, Kishinev (1985), pp. 10?11.
2. A. V. Arkhangel'skii and D. B. Shakhmatov, ?Splitting spaces,? Scientific-Research Seminar on General Topology (Spring Semester Sesions, Academic Year 1984/85) [in Russian], Vestnik Moskov. Univ., Ser. Mat. Mekh., No. 5, 90 (1985).
3. A. V. Arkhangel'skii and V. I. Ponomarev, Fundamentals of General Topology in Problems and Exercises [in Russian], Nauka, Moscow (1974).
4. R. Engelking, General Topology, PWN, Warsaw (1977).
5. J. L. Kelley, General Topology [Russian translation], Nauka, Moscow (1981).