Publications
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
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
Exploring QT variability dependence from heart rate in coma and brain death on pediatric patients. In: Computing in Cardiology. Vol 40.; 2013. 6. p. 61-64p. Edit
Sur certains systèmes d'équations avec contraintes dans un groupe libre. Portugal. Math.. 1999;56:409-417.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
[2008-21] Rational Codes and Free Profinite Monoids .Edit
On the irreducibility of pseudovarieties of semigroups. Journal of Pure and Applied Algebra. 2016;220(4):1517-1524.Edit
Monoids respecting $n$-chains of intervals. J. Algebra. 1997;187:183-202.Edit
Idempotent-generated semigroups and pseudovarieties. Proceedings of the Edinburgh Mathematical Society. 2011;54:545-568.Edit
ARFIMA-GARCH Modeling of HRV: Clinical Application in Acute Brain Injury. In: Complexity and Nonlinearity in Cardiovascular Signals. Cham: Springer International Publishing; 2017. 4. p. 451-468p. Edit
Some algorithms on the star operation applied to finite languages. Semigroup Forum. 1984;28:187-197.Edit
[2004-21] Tameness of pseudovariety joins involving R .Edit
A notion of branching rank for semilattices with descending chain condition. Order. 1988;4:397-409.Edit
Reducibility vs. definability for pseudovarieties of semigroups. International Journal of Algebra and Computation. 2016;26(7):1483-1495.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
[2006-44] Pointlike sets with respect to R and J .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