We provide new proofs for the classical insertion theorems of Dowker and Michael. The proofs are geometric in nature and highlight the connection with the preservation of normality in products. Both proofs follow directly from the Kat\v{e}tov-Tong insertion theorem and we also discuss a proof of this.
@article{119148, author = {Chris Good and Ian Stares}, title = {New proofs of classical insertion theorems}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {41}, year = {2000}, pages = {139-142}, zbl = {1038.54007}, mrnumber = {1756934}, language = {en}, url = {http://dml.mathdoc.fr/item/119148} }
Good, Chris; Stares, Ian. New proofs of classical insertion theorems. Commentationes Mathematicae Universitatis Carolinae, Tome 41 (2000) pp. 139-142. http://gdmltest.u-ga.fr/item/119148/
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