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Remarks Concerning the Invariance of Baire Spaces Under Mappings. Czechoslovak Mathematical Journal, 11 (86) (1961), 381-385.
MR 0133098
[4] L. Pontrjaqin: Topological Groups. Princeton University Press, Princeton, 1946.
[5] A. L. Youngblood: Weakly Equivalent Topologies. Masters Thesis, University of Georgia, Athens, Georgia, 1965.