The structure of certain integrally closed semigroups.
On middle units in orthodox semigroups.
Sur les demi-groupes de Brouwer et Glivenko
The general form of residuated algebraic structures
Residuation Theory (Book Review by R. McFadden.
Perfect elements in Dubreil-Jacotin regular semigroups.
On ordered regular semigroups with biggest inverses.
Pointed principally ordered regular semigroups
An ordered semigroup S is said to be principally ordered if, for every x ∈ S there exists x* = max{y ∈ S | xyx ⩽ x}. Here we investigate those principally ordered regular semigroups that are pointed in the sense that the classes modulo Green's relations ℒ,ℛ,𝒟 have biggest elements which are idempotent. Such a semigroup is necessarily a semiband. In particular we describe the subalgebra of (S;*) generated by a pair of comparable idempotents that are 𝒟-related. We also prove that those 𝒟-classes...
Invariant semigroups of othodox semigroups.
On the dual space of an MS-algebra.
Sur la construction de certaines MS-algèbres
Corrigendum à l'article "Sur la construction de certaines MS-algèbres" (Port. Math., 39(1-4) (1980), 489-496)
On the MS-algebras of the unit cube
Page 1