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Keywords:
$k$-space; $k$-network; closed map; compact-covering map
$k$-space; $k$-network; closed map; compact-covering map
Summary:
We prove some closed mapping theorems on $k$-spaces with point-countable $k$-networks. One of them generalizes La\v snev's theorem. We also construct an example of a Hausdorff space $Ur$ with a countable base that admits a closed map onto metric space which is not compact-covering. Another our result says that a $k$-space $X$ with a point-countable $k$-network admitting a closed surjection which is not compact-covering contains a closed copy of $Ur$.
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