Publications
Idempotent-generated semigroups and pseudovarieties. Proceedings of the Edinburgh Mathematical Society. 2011;54:545-568.Edit
Semigroups whose idempotents form a subsemigroup. Math. Proc. Cambridge Philos. Soc.. 1992;111:241-253.Edit
Matrix mortality and the Černý-Pin conjecture. In: Developments in language theory. Vol 5583. Springer, Berlin; 2009. 6. p. 67-80p. (Lecture Notes in Comput. Sci.; vol 5583).Edit
Sur certains systèmes d'équations avec contraintes dans un groupe libre. Portugal. Math.. 1999;56:409-417.Edit
On the topological semigroup of equational classes of finite functions under composition. J. of Mult.-Valued Logic & Soft Computing. 2017;28(1):5-28.Edit
SC-hyperdecidability of $\bf R$. Theoret. Comput. Sci.. 2001;255:569-591.Edit
On pseudovarieties, varieties of languages, filters of congruences, pseudoidentities and related topics. Algebra Universalis. 1990;27:333-350.Edit
Pointlike sets with respect to $\bf R$ and $\bf J$. J. Pure Appl. Algebra. 2008;212:486-499.Edit
Minimal nonpermutative pseudovarieties of semigroups. III. Algebra Universalis. 1985;21:256-279.Edit
[2006-44] Pointlike sets with respect to R and J .Edit
The globals of pseudovarieties of ordered semigroups containing $B_2$ and an application to a problem proposed by Pin. Theor. Inform. Appl.. 2005;39:1-29.Edit
The pro-nilpotent group topology on a free group. Journal of Algebra. 2017;480:332-345.Edit
Monoids respecting $n$-chains of intervals. J. Algebra. 1997;187:183-202.Edit
[2006-20] Representation theory of finite semigroups, semigroup radicals and formal language theory .Edit
A notion of branching rank for semilattices with descending chain condition. Order. 1988;4:397-409.Edit
Some key problems on finite semigroups. Semigroup Forum. 2002;64:159-179.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
Projection methods based on grids for weakly singular integral equations. Applied Numerical Mathematics. 2017;Volume 114:47-54.Edit
[2016-26] Equidivisible pseudovarieties of semigroups .Edit