Papers in International Journals

• Couceiro, Miguel; Lehtonen, Erkko; Waldhauser, Tamás (2012) The arity gap of order-preserving functions and extensions of pseudo-Boolean functions Discrete Applied Mathematics: 160(4-5), 383-390.

• Gillibert, Pierre (2012) The possible values of critical points between varieties of lattices Journal of Algebra: 362, 30-55.

• Kassabov, Martin; Matucci, Francesco (2012) The Simultaneous Conjugacy Problem in Groups of Piecewise Linear Functions Groups, Geometry and Dynamics: 6(2), 279--315.

• Araújo, João; Kinyon, M. (2011) An Elegant 3-Basis for Inverse Semigroups Semigroup Forum: 82(2), 319-323.

• Gillibert, Pierre; Wehrung, F. (2011) An infinite combinatorial statement with a poset parameter Combinatorica: 31(2), 183-200.

• Araújo, João; Fernandes, Vítor Hugo; Jesus, Manuel M.; Maltcev, Victor; Mitchell, James D. (2011) Automorphisms of partial endomorphism semigroups Publicationes Mathematicae Debrecen: 79(1-2), 23-29.

• Kassabov, Martin; Matucci, Francesco (2011) Bounding the residual finiteness of free groups Proceedings of the American Mathematical Society: 139(7), 2281--2286.

• Lehtonen, Erkko; Szendrei, Ágnes (2011) Clones with finitely many relative R-classes Algebra Universalis: 65, 109-159.

• Araújo, João; Mitchell, James D.; Schneider, Csaba (2011) Groups that together with any transformation generate regular semigroups or idempotent generated semigroups Journal of Algebra: 343(1), 93-106.

• Araújo, João; Kinyon, M. (2011) Independent axiom systems for nearlattices Czechoslovak Mathematical Journal: 61(4), 975-992.

• Geangu, Elena; Hauf, Petra; Bhardwaj, Rishi; Bentz, Wolfram (2011) Infant Pupil Diameter Changes in Response to Others' Positive and Negative Emotions PLoS One: 6, e27132.

• 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.

• Araújo, João; Kinyon, M.; Konieczny, J. (2011) Minimal Paths in the Commuting Graphs of Semigroups  European Journal of Combinatorics: 32, 178-197.

• 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.

• Araújo, João; Malheiro, António (2011) On finite complete presentations and exact decompositions of semigroups Communications in Algebra: 39, 10, 3866--3878.

• Kwuida, Léonard; Lehtonen, Erkko (2011) On the homomorphism order of labeled posets Order: 28, 251-265.

• André, Jorge M.; Araújo, João; Konieczny, J. (2011) Regular centralizers of idempotent transformations Semigroup Forum: 82(2), 307-318.

• Couceiro, Miguel; Lehtonen, Erkko (2011) Self-commuting lattice polynomial functions on chains Aequationes mathematicae: 81(3), 263-278.

• Bleak, Collin; Kassabov, Martin; Matucci, Francesco (2011) Structure theorems for groups of homeomorphisms of the circle International Journal of Algebra and Computation: 21(6), 1007--1036.

• 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.

• Jedlicka, P.; Kinyon, M.; Vojtechovsky, P. (2011) The structure of commutative automorphic loops Transactions of the American Mathematical Society: 363(1), 365-384.

• 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.

• Araújo, João; Edmundo, M.; Givant, S. (2011) v*-algebras, Independence Algebras and Logic International Journal on Algebra and Computation: 21, 7, 1237-1257.

• Lehtonen, Erkko (2010) A note on minors determined by clones of semilattices Novi Sad Journal of Mathematics: 40(3), 75-81.

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

• Araújo, João; Dobson, Edward; Konieczny, Janusz (2010) Automorphisms of Endomorphism Semigroups of Reflexive Digraphs Mathematische Nachrichten: 283(7), 1-26.

• Lehtonen, Erkko (2010) Characterization of preclones by matrix collections Asian-European Journal of Mathematics: 3(3), 457-473.

• Lehtonen, Erkko (2010) Closed classes of functions, generalized constraints, and clusters Algebra Universalis: 63(2-3), 203-234.

• Foldes, Stephan; Lehtonen, Erkko (2010) Column-partitioned matrices over rings without invertible transversal submatrices Ars Combinatoria: 97, 33-39.

• Medeiros, Paulo (2010) Compatible total orders on bisimple inverse w-semigroups Semigroup Forum - Volume 81: Issue1, 200-216.

• Araújo, João; McCune, William (2010) Computer Solutions of Problems in Inverse Semigroups Communications in Algebra: 38(3), 1104-1121.

• Araújo, João; Bunau, P. V.; Mitchell, James D.; Neunhoeffer, M. (2010) Computing Automorphisms of Semigroups Journal of Symbolic Computation: 45(3), 373-392.

• 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.

• Matucci, Francesco (2010) Mather invariant in groups of piecewise-linear homeomorphisms Trends in Mathematics, Combinatorial and Geometric Group Theory, 251-260.

• Lehtonen, Erkko; Nešetril, Jaroslav (2010) Minors of Boolean functions with respect to clique functions and hypergraph homomorphisms European Journal of Combinatorics: 31(8), 1981-1995.

• Bentz, Wolfram (2010) Optimal Packings of 13 and 46 Unit Squares in a Square Electronic Journal of Combinatorics: 17 (2), #R126.

• Lehtonen, Erkko; Szendrei, Ágnes (2010) The submaximal clones on the three-element set with finitely many relative R-classes Discussiones Mathematicae - General Algebra and Applications: 30(1), 7-33.

• Araújo, João; Konieczny, Janusz (2009) Automorphisms of Endomorphism Monoids of 1-Simple Free Algebras Communications in Algebra: 37(1), 83-94.

• Martins, Rachel (2009) Categorified noncommutative manifolds International journal of modern physics A: 24(15), 2802-2819.

• 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.

• Gillibert, Pierre (2009) Critical points of pairs of varieties of algebras International Journal of Algebra and Computation: 19(1), 1-40.

• Araújo, João; Wehrung, Friedrich (2009) Embedding properties of endomorphism semigroups Fundamenta Mathematicae: 202, 125-146.

• 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.

• Lehtonen, Erkko; Szendrei, Ágnes (2009) Equivalence of operations with respect to discriminator clones Discrete Mathematics: 309(4), 673-685.

• Matucci, Francesco (2009) Finite solvable groups whose Quillen complex is Cohen-Macaulay Journal of Algebra: 322(4), 969-982.