On a problem of Nogura about the product of Fréchet-Urysohn $\langle \alpha_4\rangle$-spaces
Costantini, Camillo
Commentationes Mathematicae Universitatis Carolinae, Tome 40 (1999), p. 537-549 / Harvested from Czech Digital Mathematics Library
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Assuming Martin's Axiom, we provide an example of two Fréchet-Urysohn $\langle\alpha_4\rangle$-spaces, whose product is a non-Fréchet-Urysohn $\langle\alpha_4\rangle$-space. This gives a consistent negative answer to a question raised by T. Nogura.

Publié le : 1999-01-01
Classification:  03E50,  54A20,  54A35,  54B10,  54D55,  54D80,  54G15,  54G20 
@article{119109,
     author = {Camillo Costantini},
     title = {On a problem of Nogura about the product of Fr\'echet-Urysohn $\langle \alpha\_4\rangle$-spaces},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {40},
     year = {1999},
     pages = {537-549},
     zbl = {1010.54041},
     mrnumber = {1732482},
     language = {en},
     url = {http://dml.mathdoc.fr/item/119109}
}

Costantini, Camillo. On a problem of Nogura about the product of Fréchet-Urysohn $\langle \alpha_4\rangle$-spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 40 (1999) pp. 537-549. http://gdmltest.u-ga.fr/item/119109/

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