Publications
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
Equidivisible pseudovarieties of semigroups. Publicationes Mathematicae. 2017;90(3-4):435-453.Edit
Tameness of pseudovarieties of semigroups. S\=urikaisekikenky\=usho Kōky\=uroku. 2000:8-16.Edit
Minimal nonpermutative pseudovarieties of semigroups. III. Algebra Universalis. 1985;21:256-279.Edit
On iterated semidirect products of finite semilattices. J. Algebra. 1991;142:239-254.Edit
A sequence of weakly monotonic automata with increasing level. Int. J. Algebra. 2013;7:91-100.Edit
Rational codes and free profinite monoids. J. Lond. Math. Soc. (2). 2009;79:465-477.Edit
Pseudovariety joins involving $\scr J$-trivial semigroups. Internat. J. Algebra Comput.. 1999;9:99-112.Edit
Incremental DFA Minimisation. RAIRO - Theoretical Informatics and Applications. 2014;48:173-186.Edit
Residually finite congruences and quasi-regular subsets in uniform algebras. Portugal. Math.. 1989;46:313-328.Edit
An automata-theoretic approach to the word problem for ω-terms over $\ssfR$. Theoret. Comput. Sci.. 2007;370:131-169.Edit
Free profinite semigroups over semidirect products. Izv. Vyssh. Uchebn. Zaved. Mat.. 1995:3-31.Edit
Implicit operations on certain classes of semigroups. In: Semigroups and their applications (Chico, Calif., 1986). Reidel, Dordrecht; 1987. 1. p. 1-11p. Edit
José Morgado: in memoriam. Bol. Soc. Port. Mat.. 2004:1-18.Edit
Reducibility of pointlike problems. Semigroup Forum. 2017;94(2):325-335.Edit
Commutative positive varieties of languages. Acta Cybernetica. 2017;23(1):91-111.Edit
On the power semigroup of a finite semigroup. Portugal. Math.. 1992;49:295-331.Edit
New decidable upper bound of the second level in the Straubing-Thérien concatenation hierarchy of star-free languages. Discrete Math. Theor. Comput. Sci.. 2010;12:41-58.Edit
Sur certains systèmes d'équations avec contraintes dans un groupe libre–-addenda. Port. Math. (N.S.). 2001;58:379-387.Edit
On the decidability of iterated semidirect products with applications to complexity. Proc. London Math. Soc. (3). 2000;80:50-74.Edit
Overlapping of words in rational languages. In: Combinatorics on words (Waterloo, Ont., 1982). Academic Press, Toronto, ON; 1983. 1. p. 119-131p. Edit