On expandable discrete collections

Pseudonormality and starcompactness of $\sigma $-products

“…Theorem A (Kombarov [9]). Let S = {X α |α ∈ Ω} be a family of spaces such that |Ω| ≥ ω 1 and let σ = σ(S).…”

“…In 1996, Kombarov [9] proved that if Y is a τ -envelope of spaces X α , α ∈ Ω, |Ω| ≥ max{ω 1 , τ}, then a subspace Y {x} is not pseudonormal for every x ∈ Y . In particular he obtained the following.…”