Publications
The ω-inequality problem for concatenation hierarchies of star-free languages. Forum Mathematicum. 2018;30:663-679.Edit
On regular implicit operations. Portugal. Math.. 1993;50:35-61.Edit
Iterated periodicity over finite aperiodic semigroups. European J. Combin.. 2014;37:115-149.Edit
Some key problems on finite semigroups. Semigroup Forum. 2002;64:159-179.Edit
Arfima-Garch Modeling of Hrv: Clinical Application in Acute Brain Injury Springer International Publishing 2017.Edit
On finite simple semigroups. Proc. Edinburgh Math. Soc. (2). 1991;34:205-215.Edit
Infinite-vertex free profinite semigroupoids and symbolic dynamics. J. Pure Appl. Algebra. 2009;213:605-631.Edit
[2015-34] Representations of relatively free profinite semigroups, irreducibility, and order primitivity .Edit
On hyperdecidable pseudovarieties of simple semigroups. Internat. J. Algebra Comput.. 2000;10:261-284.Edit
On a problem of Brzozowski and Fich. In: Semigroups and applications (St. Andrews, 1997). World Sci. Publ., River Edge, NJ; 1998. 1. p. 1-17p. Edit
The join of the pseudovarieties of $\scr R$-trivial and $\scr L$-trivial monoids. J. Pure Appl. Algebra. 1989;60:129-137.Edit
On the hyperdecidability of semidirect products of pseudovarieties. Comm. Algebra. 1998;26:4065-4077.Edit
Subword complexity of profinite words and subgroups of free profinite semigroups. Internat. J. Algebra Comput.. 2006;16:221-258.Edit
Generalized varieties of commutative and nilpotent semigroups. Semigroup Forum. 1984;30:77-98.Edit
On the irreducibility of pseudovarieties of semigroups. Journal of Pure and Applied Algebra. 2016;220(4):1517-1524.Edit
The mathematician Hugo Ribeiro. Portugal. Math.. 1995;52:1-14.Edit
Semidirect products with the pseudovariety of all finite groups. In: Words, languages & combinatorics, III (Kyoto, 2000). World Sci. Publ., River Edge, NJ; 2003. 1. p. 1-21p. Edit
Reducibility vs. definability for pseudovarieties of semigroups. International Journal of Algebra and Computation. 2016;26(7):1483-1495.Edit
Presentations of Schützenberger groups of minimal subshifts. Israel J. Math.. 2013;196:1-31.Edit