15 citations · 34 across the 8 of their papers we have counts for
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Varieties of De Morgan monoids: covers of atoms
T. Moraschini, J. G. Raftery, J. J. Wannenburg
The variety DMM of De Morgan monoids has just four minimal subvarieties. The join-irreducible covers of these atoms in the subvariety lattice of DMM are investigated. One of the tw…
Varieties of De Morgan monoids: minimality and irreducible algebras
T. Moraschini, J. G. Raftery, J. J. Wannenburg
It is proved that every finitely subdirectly irreducible De Morgan monoid A (with neutral element e) is either (i) a Sugihara chain in which e covers not(e) or (ii) the union of an…
Epimorphisms, definability and cardinalities
T. Moraschini, J. G. Raftery, J. J. Wannenburg
Generalizing a theorem of Campercholi, we characterize, in syntactic terms, the ranges of epimorphisms in an arbitrary class of similar first-order structures (as opposed to an ele…