Papers in International Journals

• Gomes, Gracinda M. S.; Ana-Catarina C. Monteiro (2024) Formations and i-Fitting classes of inverse semigroups, congruences and languages Semigroup Forum: 109 (1), 87-115.

• Gomes, Gracinda M. S.; Ana-Catarina C. Monteiro (2023) Formations of orthodox semigroups Semigroup Forum: 107, 651–679.

• Gomes, Gracinda M. S.; Nobre, Isabel J. (2022)  Formations of inverse semigroups Semigroup Forum: 105, 217–243.

• Gomes, Gracinda M. S.; Bernardo H. Fernandes (2021)  omega sharp algebras Communications in Algebra: 49 (9), 3969–3999.

• Gomes, Gracinda M. S.; Bernardo H. Fernandes (2021) A topological shuttle between inequalities and pseudoinequalities Semigroup Forum: 102, no. 3, 916–924.

• Gouveia, M. J.; Lehtonen, Erkko (2021) Permutation reconstruction from a few large patterns Electronic Journal of Combinatorics: 28(3), #P3.41.

• Ghilardi S.; Gouveia, M. J.; Santocanale L (2019) Fixed-Point Elimination in the Intuitionistic Propositional Calculus ACM Transactions on Computational Logic: 21(1), 1-37.

• Branco, Mário J. J.; Gomes, Gracinda M. S.; Silva, Pedro V. (2019) On the semigroup rank of a group Semigroup Forum: 99, 568-578.

• Araújo, João; Gomes, Gracinda M. S.; Bentz, Wolfram (2018) Congruences on direct products of transformation and matrix monoids Semigroup Forum: 97, 384-416.

• Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria; Wang, Yanhui (2018) Ehresmann monoids: adequacy and expansions Journal of Algebra: 513, 344-367.

• Soares, Filipa; Silva, Pedro V.; Volkov, Mikhail V. (2018) Local finiteness for Green's relations in semigroup varieties Communications in Algebra: 40 (10), 4625-4653.

• Branco, Mário J. J.; Gomes, Gracinda M. S.; Silva, Pedro V.  (2017) Takahasi semigroups Forum Mathematicum: 29(5), 1145-1161.

• Soares, Filipa; Silva, Pedro V. (2016) Howson's Property for Semidirect Products of Semilattices by Groups Communications in Algebra: 44, 2482-2494.

• Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria (2015) Ehresmann monoids J. Algebra: 443, 349–382.

• Gomes, Gracinda M. S.; Santa-Clara, Catarina; Soares, Filipa (2015) The semigroup ring of a restriction semigroup with an inverse skeleton Semigroup Forum: 90 (2015), no. 2, 449–474.

• Craig, A.; Gouveia, M. J.; Haviar, M. (2015) TiRS graphs and TiRS frames: a new setting for duals of canonical extensions , (in press).

• Gouveia, M. J.; Priestley, H. A. (2014) Canonical extensions and profinite completions of semilattices and lattices  Order: 31(2), 189-216.

• Gomes, Gracinda M. S.; Ruskuc, Nik (2014) John Macintosh Howie: Work and Legacy Semigroup Forum: 89(1), 2-19.

• Bentz, Wolfram; Sequeira, Luís (2014) Taylor's modularity conjecture holds for linear idempotent varieties Algebra Universalis: 71(2), 101-107.

• Gouveia, M. J.; Priestley, H. A. (2013) Profinite completions and canonical extensions of semilattice reducts of distributive lattices Houston J. Math.: 39(4), 1117-1136.

• Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria (2011) Left adequate and left Ehresmann monoids  International Journal of Algebra and Computation: 21(7), 1259-1284.

• Gomes, Gracinda M. S.; Gould, Victoria (2011) Left adequate and left Ehresmann monoids II Journal of Algebra: 348(1), 171-195.

• Davey, B. A.; Gouveia, M. J.; Haviar, M.; Priestley, H. A. (2011) Multisorted dualisability: change of base Algebra Universalis: 66(4), 331-336.

• Davey, B.; Gouveia, M. J.; Haviar, M.; Priestley, H. A. (2011) Natural extensions and profinite completions of algebras Algebra Universalis: 66(3), 205-241.

• Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2011) The cardinal and the idempotent number of various monoids of transformations on a finite chain Bulletin of the Malaysian Mathematical Sciences Society: 34(1), 79–85.

• McAlister, D. B.; Soares, Filipa (2011) Tiling semigroups of n-dimensional hypercubic tilings Communications in Algebra: 39(6), 2002-2023.

• Gouveia, M. J.; Haviar, M. (2011) Transferral of entailment in duality theory II: strong dualisability  Czechoslovak Mathematical Journal: 61(2), 401-417.

• Gouveia, M. J.; Haviar, M. (2011) Transferral of entailment in duality theory: dualisability  Czechoslovak Mathematical Journal: 61(1), 41-63.

• Iglésias, Laura; Santa-Clara, Catarina; Silva, Fernando C. (2011) Unified Min-Max and Interlacing Theorems for Linear Operators Linear and Multilinear Algebra: 59(6), 651-669.

• Gouveia, M. J. (2010) A note on profinite completions and canonical extensions  Algebra Universalis: 64(1-2), 21-23.

• Branco, Mário J. J.; Gould, Victoria; Gomes, Gracinda M. S. (2010) Extensions and covers for semigroups whose idempotents form a left regular band Semigroup Forum: 81, 51-70.

• Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2009) Congruences on monoids of transformations preserving the orientation on a finite chain Journal of Algebra: 321(3), 743–757.

• Branco, Mário J. J.; Pin, J.-E. (2009) Equations defining the polynomial closure of a lattice of regular languages Lecture Notes in Computer Science: 5556, 115-126.

• Mermut, Engin; Santa-Clara, Catarina; Smith, Patrick F. (2009) Injectivity Relative to Closed Submodules Journal of Algebra: 321(2), 548-557.

• Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (2009) Membership of AvG for classes of finite weakly abundant semigroups Periodica Mathematica Hungarica: 59(1), 9-36.

• Soares, Filipa; McAlister, D. B. (2009) One-dimensional tiling semigroups and factorial languages Communications in Algebra: 37(1), 276-295.

• Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (2009) The free ample monoid International Journal of Algebra and Computation: 19(4), 527-554.

• Branco, Mário J. J.; Gomes, Gracinda M. S. (2009) The generalized Szendrei expansion of an R-unipotent semigroup Acta Mathematica Hungarica: 123(1-2), 11-26.

• Gomes, Gracinda M. S.; Gould, Victoria (2008) Fundamental semigroups having a band of idempotents Semigroup Forum: 77, 279-299.

• Gomes, Gracinda M. S.; Maria B. Szendrei (2007) Almost factorizable weakly ample semigroups Communications in Algebra: 35 (11), 3503-3523.

• Branco, Mário J. J. (2007) Deterministic concatenation product of languages recognized by finite idempotent monoids Semigroup Forum: 74, n. 3, 379-409.

• Gomes, Gracinda M. S.; Szendrei, Maria B. (2007) Even covers of left ample semigroups Semigroup Forum: 74(2), 293-305.

• Fountain, John B.; Gomes, Gracinda M. S. (2006) Finite abundant semigroups in which the idempotents form a subsemigroup Journal of Algebra: 295, 303-313.

• Gomes, Gracinda M. S.; Pin, J.-E.; Sezinando, Helena (2006) Presentations of the Schützenberger product of n groups Communications in Algebra: 34 (4), 1213-1235.

• Fountain, J.B.; Gomes, Gracinda M. S. (2006) Proper covers of ample monoids Proc. Edinb. Math. Soc.: 49, 277-289.

• Gomes, Gracinda M. S. (2006) The generalized prefix expansion of a weakly left ample semigroup Semigroup Forum: 72 (3), 387-403.

• Branco, Mário J. J. (2006) Two algebraic approaches to variants of the concatenation product Theoret. Comput. Sci.: 369, 406-426.

• Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2005) Congruences on monoids of order-preserving or order-reversing transformations on a finite chain Glasgow Mathematical Journal: 47, 413-424.

• Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2005) Presentations for some monoids of partial transformations on a finite chain Communications in Algebra: 33, 587-604.

• Gomes, Gracinda M. S. (2005) Proper extensions of weakly left ample semigroups Acta Math Hungarica: 109 (1-2), 33-51.