77 citations · 154 across the 22 of their papers we have counts for
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math.GR2016★ 2 cited
Reducibility versus definability for pseudovarieties of semigroups
J. Almeida, O. Klíma
It is easy to show that a pseudovariety which is reducible with respect to an implicit signature for the equation can also be defined by -identities. We present severa…
math.GR2016★ 6 cited
Equidivisible pseudovarieties of semigroups
Jorge Almeida, Alfredo Costa
We give a complete characterization of pseudovarieties of semigroups whose finitely generated relatively free profinite semigroups are equidivisible. Besides the pseudovarieties of…
math.GR2016★ 3 cited
The omega-inequality problem for concatenation hierarchies of star-free languages
J. Almeida, O. Klíma, M. Kunc
The problem considered in this paper is whether an inequality of omega-terms is valid in a given level of a concatenation hierarchy of star-free languages. The main result shows th…