On a dense -diagonal.
On a modified game of Sierpiński
On a problem of Banach
On completeness of quasi-pseudometric spaces.
On complexity of metric spaces
On coupled random fixed point results in partially ordered metric spaces
On existence and uniqueness of Chebyshev center of bounded set in a special geodesic space.
On half-completion and bicompletion of quasi-metric spaces
We characterize the quasi-metric spaces which have a quasi-metric half-completion and deduce that each paracompact co-stable quasi-metric space having a quasi-metric half-completion is metrizable. We also characterize the quasi-metric spaces whose bicompletion is quasi-metric and it is shown that the bicompletion of each quasi-metric compatible with a quasi-metrizable space is quasi-metric if and only if is finite.
On indecomposability and composants of chaotic continua
A homeomorphism f:X → X of a compactum X with metric d is expansive if there is c > 0 such that if x,y ∈ X and x ≠ y, then there is an integer n ∈ ℤ such that . A homeomorphism f: X → X is continuum-wise expansive if there is c > 0 such that if A is a nondegenerate subcontinuum of X, then there is an integer n ∈ ℤ such that . Clearly, every expansive homeomorphism is continuum-wise expansive, but the converse assertion is not true. In [6], we defined the notion of chaotic continua of homeomorphisms...
On metrizable abelian groups with a completeness-type property
On Polish spaces Lipschitz universal for separable metric spaces
On some applications of infinite-dimensional manifolds to the theory of shape
On some dense subspaces of topological linear spaces
On subcompactness and countable subcompactness of metrizable spaces in ZF
We show in ZF that: (i) Every subcompact metrizable space is completely metrizable, and every completely metrizable space is countably subcompact. (ii) A metrizable space is countably compact if and only if it is countably subcompact relative to . (iii) For every metrizable space , the following are equivalent: (a) is compact; (b) for every open filter of , ; (c) is subcompact relative to . We also show: (iv) The negation of each of the statements, (a) every countably subcompact metrizable...
On the convergence of certain sequences and some applications
On the differentiation theorem in metric groups
On the generalized property
On the structure of the dual complexity space: The general case.