I 2023, an invited talk during the “1st Workshop on Graph Theory”, Johannesburg University – South Africa;

VII 2020, an invited talk during the “Groups, Graphs, Growth and Complexity”, Budapest – Hungary; (canceled due to pandemic);

IX 2019, a plenary talk during “28th Cycles and Colourings Conference”, Smokovce – Slovakia;

IX 2018, an invitation for “Symmetry Breaking in Discrete Structures” in Banff International Research Station, Oaxaca – Mexico;

V 2018, an invited talk during the “Graphs, groups, and more” Conference, Koper – Slovenia;

II 2018, coauthor Winter School on Graph Theory, Ferdowsi University of Mashhad – Iran;

IX 2022, Majority edge-colourings of graphs, “Maribor Graph Theory Conference”, Maribor – Slovenia;

IV 2022, Proper arc-colourings of symmetric digraphs, invited talks at Ljubljana University, Ljubljana – Slovenia;

IX 2021, Distinguishing colourings of symmetric digraphs, “29th Cycles and Colourings Conference”, Kosice – Slovakia;

II 2020, Distinguishing colourings of regular graphs, “Symmetries of Discrete Objects Conference”, Rotorua – New Zeland;

XII 2019, Asymmetric Colourings of Infinite Graphs, Montanuniversität Leoben – Austria;

X 2019, Symmetry Breaking in Graphs and 1-2-3 Conjecture; On Asymmetric Proper Colouring; Asymmetric Colourings of Infinite Graphs; invited talks at Maribor, Ljubljana Universities and at University na Primorsku in Koper – Slovenia;

VI 2019, Distinguishing Colouring of Maps, “9th Slovenian International Conference on Graph Theory”, Bled – Slovenia;

VI 2017, Improving upper bounds for the distinguishing index of infinite graphs, Malta Conference in Graph Theory and Combinatorics, Malta;

IX 2016, Distinguishing graphs by proper colourings, “6th Polish Combinatorial Conference”, Będlewo – Poland;

VII 2016, Symmetry breaking in graphs, “International Workshop On Graph Labeling”, Kraków – Poland;

XI 2015, Symmetry breaking in graphs, LaBRI Bordeaux – France;

IX 2015, Distinguishing infinite graphs by edge colourings, “Coloring Independent Domination”, Szklarska Poręba – Poland;

III 2015, Distinguishing infinite graphs by edge colourings, “Fifth International Conference on Combinatorics”, Graph Theory and Applications”, Elgersburg – Germany;

IX 2014, Distinguishing graphs by edge colourings, “5th Polish Combinatorial Conference”, Będlewo – Poland;

VII 2014, The distinguishing index of a graph, University of Mining and Technology, Freiberg – Germany;

V 2014, Distinguishing graphs by total colourings, “18th C5 Graph Theory”, Rathen – Germany;

XII 2013, Symmetry breaking by edge-colourings, “Freiberger Graphentheorie-Tage”, Freiberg – Germany;

IX 2013, Symmetry breaking in infinite graphs, “Cycles and Colourings”, Smokowiec – Slovakia;

VI 2013, The distinguishing index of a graph, University of Maribor – Slovenia;

V 2013, On colour walks in graphs, “17th C5 Graph Theory”, Rathen – Germany;

XII 2012, Endomorphism breaking in graphs, “Freiberger Graphentheorie-Tage”, Freiberg – Germany;

IX 2012, Endomorphism breaking in graphs, “4-th Polish Combinatorial Conference”, Będlewo – Poland;

VI 2012, Daltonists can distinguish colour palettes, Montanuniversität Leoben – Austria;

VI 2011, On the total-neighbor-distinguishing index by sums, “7th Slovenian International Conference on Graph Theory”, Bled – Slovenia;

VI 2011, On packing of graphs, digraphs and hypergraphs, Montanuniversität Leoben – Austria;

V 2011, On the total-neighbor-distinguishing index by sums, “14th C5 Graph Theory”, Rathen – Germany;

XII 2010, On the adjacent vertex distinguishing index by sums in total proper coloring, “Freiberger Graphentheorie-Tage”, Freiberg – Germany;

VII 2010, On the adjacent vertex distinguishing index by the sum in total proper coloring, “8 th France Combinatorial Conference”, Paris – France;

VI 2010, On packing of graphs, digraphs and hypergraphs, LaBRI - Laboratoire Bordelais de Recherche en Informatique, Bordeaux – France;

IX 2009, Coloring chip configurations on graphs and digraphs, “Colourings, Independence and Domination”, Szklarska Poręba – Poland;

IX 2008, On packing of hypergraphs, “Cycles and Colourings”, Tatranska Strba – Slovakia;

IX 2007, A note on an embedding problem in transitive tournaments, “Colourings, Independence and Domination”, Karpacz – Poland;

IX 2004, Packing and embedding of digraphs into transitive tournaments, “2nd Combstru Workshop”, Wenecja – Italy;

IX 2004, Packing of digraphs into transitive tournaments, “Cycles and Colourings”, Tatranska Strba – Slovakia;

IX 2003, Problems of packing into the transitive tournament, “Cycles and Colourings”, Stara Lesna – Slovakia;

V 2003, Packing of three copies of digraphs into the transitive tournament, “7th C5 Graph Theory”, Rathen – Germany;

XI 2002, Packing of two digraphs into the transitive tournament, “3in1 Graphs”, Krynica – Poland;

V 2002, Packing of two copies of digraphs into the transitive tournament, “6th C5 Graph Theory”, Rathen – Germany;

IX 2001, On cyclically embeddable (n,n)-graphs, “Cycles and Colourings”, Stara Lesna – Slovakia;

V 2001, On embeddable graphs, “On discrete mathematics and informatics”, Kosice – Slovakia;