1. R. Engelking, General Topology, PWN, Warsaw (1977).
2. H. Herrlich, ?Quotienten geordneter Räume und Folgenkonvergenz,? Fund. Math.,61, 79?81 (1967).
3. K. Kuratowski and A. Mostowskii, Set Theory, North-Holland (1968).
4. A. V. Arkhangel'skii and V. I. Ponomarev, Foundations of General Topology in Problems and Exercises [in Russian], Nauka, Moscow (1974).
5. B. A. Efimov, ?Diadic bicompacta,? Tr. Mosk. Mat. 0-va,14, 211?247 (1965).