Key points are not available for this paper at this time.
have become important in homotopy theory, and our basic objective is to show that such constructions do not lead outside the class SW (Theorem 3). The first section is concerned with the smaller class Wo, consisting of all spaces which have the homotopy type of a countable CW-complex. ??1 and 2 are independent of each other. The basic reference for this paper is J. H. C. Whitehead 15. 1. The class Wvo.
John Milnor (Thu,) studied this question.