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Keywords:
separable; c.c.c.; $\sigma$-centered base; $\sigma$-$n$-linked base; $I_n$-em\-bed\-ding; $I_{<\omega}$-em\-bed\-ding; product; Martin's Axiom; $C_p$-spaces
Summary:
We characterize spaces with $\sigma$-$n$-linked bases as specially embedded subspaces of separable spaces, and derive some corollaries, such as the $\bold c$-productivity of the property of having a $\sigma$-linked base.
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