Cardinality of open \(\sigma\)-compact sets in the space of noncompact subgroups of a topological group. (English. Russian original) Zbl 0723.22004
Ukr. Math. J. 40, No. 6, 679-683 (1988); translation from Ukr. Mat. Zh. 40, No. 6, 803-807 (1988).
Reviewer: M.G.Tkachenko (Tver)