On automorphism groups of cyclically ordered sets.
On automorphism groups of non-associative Boolean rings.
On automorphism groups of planar lattices
The structure of automorphisms of planar lattices is analyzed.
On automorphisms of Boolean algebras embedded in P (ω)/fin
We prove that, under CH, for each Boolean algebra A of cardinality at most the continuum there is an embedding of A into P(ω)/fin such that each automorphism of A can be extended to an automorphism of P(ω)/fin. We also describe a model of ZFC + MA(σ-linked) in which the continuum is arbitrarily large and the above assertion holds true.
On automorphisms of the lattice of quasivarieties of lattice-ordered groups
On axiom systems of pseudo-BCK algebras.
On B-algebras
On Banach's fixed point theorem and formal balls.
On BE-semigroups.
On BF-algebras
On binary coproducts of frames
The structure of binary coproducts in the category of frames is analyzed, and the results are then applied widely in the study of compactness, local compactness (continuous frames), separatedness, pushouts and closed frame homomorphisms.
On bisemilattices. I
On blockers in bounded posets.
On Boolean modus ponens.
An abstract form of modus ponens in a Boolean algebra was suggested in [1]. In this paper we use the general theory of Boolean equations (see e.g. [2]) to obtain a further generalization. For a similar research on Boolean deduction theorems see [3].
On Boolean partial differential equations
On bounding congruences in some algebras having the lattice structure
On BPI Restricted to Boolean Algebras of Size Continuum
(i) The statement P(ω) = “every partition of ℝ has size ≤ |ℝ|” is equivalent to the proposition R(ω) = “for every subspace Y of the Tychonoff product the restriction |Y = Y ∩ B: B ∈ of the standard clopen base of to Y has size ≤ |(ω)|”. (ii) In ZF, P(ω) does not imply “every partition of (ω) has a choice set”. (iii) Under P(ω) the following two statements are equivalent: (a) For every Boolean algebra of size ≤ |ℝ| every filter can be extended to an ultrafilter. (b) Every Boolean algebra of...
On branchwise implicative BCI-algebras.
On Butler -groups decomposing over two base elements
A -group is a sum of a finite number of torsionfree Abelian groups of rank , subject to two independent linear relations. We complete here the study of direct decompositions over two base elements, determining the cases where the relations play an essential role.
On Carathéodory vector lattices