We provide a characterisation of monotone normality with an analogue of the Tietze-Urysohn theorem for monotonically normal spaces as well as answer a question due to San-ou concerning the extension of Urysohn functions in monotonically normal spaces. We also extend a result of van Douwen, giving a characterisation of $K_0$-spaces in terms of semi-continuous functions, as well as answer another question of San-ou concerning semi-continuous Urysohn functions.
@article{118785, author = {Ian Stares}, title = {Monotone normality and extension of functions}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {36}, year = {1995}, pages = {563-578}, zbl = {0882.54012}, mrnumber = {1364497}, language = {en}, url = {http://dml.mathdoc.fr/item/118785} }
Stares, Ian. Monotone normality and extension of functions. Commentationes Mathematicae Universitatis Carolinae, Tome 36 (1995) pp. 563-578. http://gdmltest.u-ga.fr/item/118785/
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