References
[I] Impens, C.: Real functions as traces of infinite polynomials Math. Ann.284, 63–73 (1989)
[Sch] Schubert, H.: Topologic, Stuttgart: Teubner 1964
[St-Se] Steen, L.A., Scebach, J.A.: Counterexamples in topology. New York Heidelberg Berlin, Springer Verlag 1978
[W] Willard, S.: General topology. London Sydney: Addison-Wesley Publishing Company 1970