Publications
Implicit operations on certain classes of semigroups. In: Semigroups and their applications (Chico, Calif., 1986). Reidel, Dordrecht; 1987. 1. p. 1-11p. 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
The mathematician Hugo Ribeiro. Portugal. Math.. 1995;52:1-14.Edit
Complete kappa-reducibility of pseudovarieties of the form DRH. International Journal of Algebra and Computation. 2017;27(02):189-236.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
Globals of pseudovarieties of commutative semigroups: the finite basis problem, decidability and gaps. Proc. Edinb. Math. Soc. (2). 2001;44:27-47.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
The equation $\bf PX=\bf PJ$. In: Proceedings of the International Symposium on the Semigroup Theory and its Related Fields (Kyoto, 1990). Shimane Univ., Matsue; 1990. 1. p. 1-11p. Edit
Description and analysis of a bottom-up DFA minimization algorithm. Inform. Process. Lett.. 2008;107:52-59.Edit
Incremental DFA Minimisation. In: Domaratzki M, Salomaa K, editors. Proceedings of the 15th International Conference on Implementation and Application of Automata (CIAA 2010). Winnipeg, MA, Canada; 2011. 3. p. 39-48p. Edit
Power exponents of aperiodic pseudovarieties. Semigroup Forum. 1999;59:18-32.Edit
Estimation of hedonic responses from descriptive skin sensory data by chi-square minimization. Journal of Sensory Studies. 2006;21:2-19.Edit
On the irreducibility of pseudovarieties of semigroups. Journal of Pure and Applied Algebra. 2016;220(4):1517-1524.Edit
Multilead ECG Delineation Using Spatially Projected Leads From Wavelet Transform Loops. {IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING}. 2009;{56}:{1996-2005}.Edit
On power varieties of semigroups. J. Algebra. 1989;120:1-17.Edit
The pseudovariety of semigroups of triangular matrices over a finite field. Theor. Inform. Appl.. 2005;39:31-48.Edit
Free profinite $\scr R$-trivial monoids. Internat. J. Algebra Comput.. 1997;7:625-671.Edit
Presentations of Schützenberger groups of minimal subshifts. Israel J. Math.. 2013;196:1-31.Edit
Minimal nonpermutative pseudovarieties of semigroups. III. Algebra Universalis. 1985;21:256-279.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
Implicit operations and Knast's theorem. In: Semigroups (Luino, 1992). World Sci. Publ., River Edge, NJ; 1993. 1. p. 1-16p. Edit