Article
Keywords:
D-spaces; (mod$k$)-networks; cushioned collections; semi-stratifiable spaces
Summary:
Every semi-stratifiable space or strong $\Sigma$-space has a $\sigma$-cushioned (mod$k$)-network. In this paper it is showed that every space with a $\sigma$-cushioned (mod$k$)-network is a D-space, which is a common generalization of some results about D-spaces.
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