A simple geometric proof of a theorem on
A simple proof of Suzumura's extension theorem for finite domains with applications.
A simple proof of Vinogradov’s theorem on the orderability of the free product of -groups
A simplified proof of the Daniell integral extension theorem in ordered spaces
A solution of Dedekind's problem on the number of isotone Boolean functions.
A spectral construction of a treed domain that is not going-down
A strongly diagonal power of algebraic order bounded disjointness preserving operators.
A structure theorem for right invariant right holoids.
A study of independence in a set with orthogonality
A subdirectly irreducible symmetric Heyting algebra which is not simple.
A sufficient condition of full normality
We present a direct constructive proof of full normality for a class of spaces (locales) that includes, among others, all metrizable ones.
A survey of hereditary properties of graphs
In this paper we survey results and open problems on the structure of additive and hereditary properties of graphs. The important role of vertex partition problems, in particular the existence of uniquely partitionable graphs and reducible properties of graphs in this structure is emphasized. Many related topics, including questions on the complexity of related problems, are investigated.
A survey on lifting in measure theory
A ternary variety generated by lattices
A Theorem on Anti-ordered Factor-semigroups
A Theorem on Directed Quasi-Ordered Sets and Some Remarks
A topological duality for the -chains associated with the logic
In this paper we present a topological duality for a certain subclass of the -structures defined by M. M. Fidel, which conform to a non-standard semantics for the paraconsistent N. C. A. da Costa logic . Actually, the duality introduced here is focused on -structures whose supports are chains. For our purposes, we characterize every -chain by means of a new structure that we will call down-covered chain (DCC) here. This characterization will allow us to prove the dual equivalence between the...
A topological representation of polarity lattices.
A topological view of ordered groups
In this expository article we use topological ideas, notably compactness, to establish certain basic properties of orderable groups. Many of the properties we shall discuss are well-known, but I believe some of the proofs are new. These will be used, in turn, to prove some orderability results, including the left-orderability of the group of PL homeomorphisms of a surface with boundary, which are fixed on at least one boundary component.
A type of semilattice product.