Publications
The ω-inequality problem for concatenation hierarchies of star-free languages. Forum Mathematicum. 2018;30:663-679.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 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
Counting factors in words, semidirect products and power semigroups. In: Words, languages and combinatorics (Kyoto, 1990). World Sci. Publ., River Edge, NJ; 1992. 1. p. 1-15p. Edit
Semidirect product with an order-computable pseudovariety and tameness. Semigroup Forum. 2010;81:26-50.Edit
Globals of pseudovarieties of commutative semigroups: the finite basis problem, decidability and gaps. Proc. Edinb. Math. Soc. (2). 2001;44:27-47.Edit
[2004-18] The globals of pseudovarieties of ordered semigroups containing $B_2$ and an application to a proble .Edit
Complete κ-reducibility of pseudovarieties of the form DRH. International Journal of Algebra and Computation. 2017;27(2):189-235.Edit
An elementary proof that finite groups are projectively torsion-free. Portugal. Math.. 1990;47:437-444.Edit
Description and analysis of a bottom-up DFA minimization algorithm. Inform. Process. Lett.. 2008;107:52-59.Edit
Power pseudovarieties of semigroups. I, II. Semigroup Forum. 1986;33:357-373, 375-390.Edit
On Decidability of Intermediate Levels of Concatenation Hierarchies. In: 19th International Conference Developments in Language Theory (DLT 2015). Vol Developments in Language Theory, LNCS 9168. UK, Liverpool: Springer; 2015. 5. p. 58-70p. Edit
Presentations of Schützenberger groups of minimal subshifts. Israel J. Math.. 2013;196:1-31.Edit
Power exponents of aperiodic pseudovarieties. Semigroup Forum. 1999;59:18-32.Edit
Free profinite $\scr R$-trivial monoids. Internat. J. Algebra Comput.. 1997;7:625-671.Edit
On pseudovarieties of monoids. In: Semigroups, theory and applications (Oberwolfach, 1986). Vol 1320. Springer, Berlin; 1988. 1. p. 11-17p. (Lecture Notes in Math.; vol 1320).Edit
The pseudovariety of semigroups of triangular matrices over a finite field. Theor. Inform. Appl.. 2005;39:31-48.Edit
Implicit operations and Knast's theorem. In: Semigroups (Luino, 1992). World Sci. Publ., River Edge, NJ; 1993. 1. p. 1-16p. Edit
Closures of regular languages for profinite topologies. Semigroup Forum. 2014;89:20-40.Edit
Finite semigroups: an introduction to a unified theory of pseudovarieties. In: Semigroups, algorithms, automata and languages (Coimbra, 2001). World Sci. Publ., River Edge, NJ; 2002. 3. p. 3-64p. Edit
A parametric model approach for quantification of short term QT variability uncorrelated with heart rate variability. In: Murray A, editor. {30th Annual Meeting on Computers in Cardiology}. Vol {30}. {IEEE}; 2003. {. {p. 165-168p. }.Edit