January 2020 - present
Professor, University of the Free State, Bloemfontein, South Africa

March 2014 - December 2019
Associate Professor, University of the Free State, Bloemfontein, South Africa

September 2012 - February 2014 
Lecturer, University of Pretoria, Pretoria, South Africa

April 2010 - August 2012 
Postdoctoral researcher, University of KwaZulu-Natal, Durban, South Africa

October 2007 - January 2009 
Researcher, Slovak University of Technology, Bratislava, Slovakia

June 2008 - September 2008 
Postdoctoral researcher, Bandung Institute of Technology, Bandung, Indonesia

October 2004 - June 2008 
PhD study in applied mathematics, Slovak University of Technology, Bratislava, Slovakia

March 2006 - May 2006 
PhD research stay, Vienna University of Technology, Vienna, Austria

September 2004 - December 2005 
Teaching assistant, University of Trencin, Trencin, Slovakia

May 2005 
PhD study stay, University of Ostrava, Ostrava, Czech Republic

September 1999 - May 2004 
MSc and BSc study in mathematics, Constantine the Philosopher University, Nitra, Slovakia

1.     T. Vetrik, M. Abas, Multiplicative Zagreb indices of trees with given domination number, Communications in Combinatorics and Optimization 9, No. 1 (2024), 89–99.
2.     E. Swartz, T. Vetrik, General sum-connectivity index and general Randic index of trees with given maximum degree, Discrete Mathematics Letters 12 (2023), 181–188.
3.     T. Vetrik, Degree-based function index for graphs with given connectivity, Iranian Journal of Mathematical Chemistry 14, No. 3 (2023), 183–194.
4.     T. Vetrik, M. Imran, M. Knor, R. Skrekovski, The metric dimension of the circulant graph with 2k generators can be less than k, Journal of King Saud University – Science 35 (2023), 102834.
5.     E. C. M. Maritz, T. Vetrik, On the partition dimension of directed circulant graphs, Journal of Discrete Mathematical Sciences and Cryptography 26, No. 1 (2023), 1–10.
6.     T. Vetrik, General approach for obtaining extremal results on degree-based indices illustrated on the general sum-connectivity index, Electronic Journal of Graph Theory and Applications 11, No. 1 (2023), 125–133.
7.     T. Vetrik, Degree-based function index for graphs with given diameter, Discrete Applied Mathematics 333 (2023), 59–70.
8.     K. C. Das, T. Vetrik, General Gutman index of a graph, MATCH Communications in Mathematical and in Computer Chemistry 89 (2023), 583–603.
9.     T. Vetrik, General Randic index of trees with given number of branching vertices, Discrete Mathematics, Algorithms and Applications 15, No. 4 (2023), 2250107.
10.   T. Vetrik, General sum-connectivity index of trees with given number of branching vertices, Transactions on Combinatorics 12, No. 4 (2023), 227–238.
11.   D. Kuziak, E. Maritz, T. Vetrik, I. G. Yero, The edge partition dimension of graphs, Discrete Mathematics Letters 12 (2023), 34–39.
12.   T. Vetrik, M. Masre, S. Balachandran, Eccentric connectivity coindex of bipartite graphs, Discrete Mathematics, Algorithms and Applications 15, No. 1 (2023), 2250054.
13.   T. Vetrik, General eccentric distance sum of graphs with given diameter, Asian-European Journal of Mathematics 16, No. 4 (2023), 2350057.
14.   M. R. Alfuraidan, K. C. Das, T. Vetrik, S. Balachandran, General Randic index of unicyclic graphs with given diameter, Discrete Applied Mathematics 306 (2022), 7–16.
15.   T. Vetrik, General sum-connectivity index of unicyclic graphs with given diameter and girth, Discrete Mathematics, Algorithms and Applications 14, No. 4 (2022), 2150140.
16.   Y. K. Feyissa, M. Imran, T. Vetrik, N. Hunde, On the general eccentric distance sum of graphs and trees, Iranian Journal of Mathematical Chemistry 13, No. 4 (2022), 239–252.
17.   T. Vetrik, General Randic index of unicyclic graphs with given girth and diameter, Asian-European Journal of Mathematics 15, No. 9 (2022), 2250165.
18.   T. Vetrik, S. Balachandran, General Randic index of unicyclic graphs with given number of pendant vertices, Discrete Mathematics Letters 8 (2022), 83–88.
19.   T. Vetrik, M. M. M. Jaradat, M. S. Bataineh, A note on the Ramsey number for small graphs, Journal of Discrete Mathematical Sciences and Cryptography 25, No. 2 (2022), 463–470.
20.   T. Vetrik, M. Masre, S. Balachandran, Zeroth-order general Randic index of trees with given distance k-domination number, Electronic Journal of Graph Theory and Applications 10, No. 1 (2022), 247–257.
21.   E. Swartz, T. Vetrik, Survey on the general Randic index: extremal results and bounds, Rocky Mountain Journal of Mathematics 52, No. 4 (2022), 1177–1203.
22.   Y. K. Feyissa, T. Vetrik, Bounds on the general eccentric distance sum of graphs, Discrete Mathematics Letters 10 (2022), 99–106.
23.   M. Imran, T. Vetrik, On the partition dimension of infinite graphs, Mathematical Reports 24 (2022), 433–442.
24.   T. Vetrik, S. Balachandran, Zeroth-order general Randic index of trees, Boletim da Sociedade Paranaense de Matematica 40 (2022), 1–9.
25.   T. Vetrik, Study of generalized networks using graph theory, Hacettepe Journal of Mathematics and Statistics 50, No. 5 (2021), 1491–1499.
26.   M. R. Alfuraidan, K. C. Das, T. Vetrik, S. Balachandran, General sum-connectivity index of unicyclic graphs with given diameter, Discrete Applied Mathematics 295 (2021), 39–46.
27.   M. Masre, T. Vetrik, General degree-eccentricity index of trees, Bulletin of the Malaysian Mathematical Sciences Society 44 (2021), 2753–2772.
28.   T. Vetrik, Extended study of biological networks using graph theory, Proyecciones Journal of Mathematics 40, No. 5 (2021), 1211–1225.
29.   M. R. Alfuraidan, S. Balachandran, T. Vetrik, General multiplicative Zagreb indices of unicyclic graphs, Carpathian Journal of Mathematics 37, No. 1 (2021), 1–11.
30.   T. Vetrik, General degree distance of graphs, Journal of Algebra Combinatorics Discrete Structures and Applications 8, No. 2 (2021), 107–118.
31.   S. Balachandran, T. Vetrik, General multiplicative Zagreb indices of trees with given independence number, Quaestiones Mathematicae 44, No. 5 (2021), 659–668.
32.   M. Masre, T. Vetrik, On the general degree-eccentricity index of a graph, Afrika Matematika 32 (2021), 495–506.
33.   E. T. Baskoro, T. Vetrik, A note on the size Ramsey numbers for matchings versus cycles, Mathematica Bohemica 146, No. 2 (2021), 229–234.
34.   T. Vetrik, General eccentric distance sum of graphs, Discrete Mathematics, Algorithms and Applications 13, No. 4 (2021), 2150046.
35.   S. Balachandran, T. Vetrik, Exponential second Zagreb index of chemical trees, Transactions on Combinatorics 10, No. 2 (2021), 25–34.
36.   H. Deng, T. Vetrik, S. Balachandran, On the harmonic index and the signless Laplacian spectral radius of graphs, Kragujevac Journal of Mathematics 45, No. 2 (2021), 299–307.
37.   L. du Toit, S. Mukwembi, T. Vetrik, A note on the eccentric connectivity index of graphs of given diameter, Utilitas Mathematica 115 (2020), 267–274.
38.   T. Vetrik, M. Masre, General eccentric connectivity index of trees and unicyclic graphs, Discrete Applied Mathematics 284 (2020), 301–315.
39.   T. Vetrik, S. Balachandran, General multiplicative Zagreb indices of trees and unicyclic graphs with given matching number, Journal of Combinatorial Optimization 40 (2020), 953–973.
40.   M. Abas, T. Vetrik, Metric dimension of Cayley digraphs of split metacyclic groups, Theoretical Computer Science 809 (2020), 61–72.
41.   M. R. Alfuraidan, M. Imran, M. K. Jamil, T. Vetrik, General multiplicative Zagreb indices of graphs with bridges, IEEE Access 8 (2020), 118725–118731.
42.   T. Vetrik, On the metric dimension of directed and undirected circulant graphs, Discussiones Mathematicae Graph Theory 40 (2020), 67–76.
43.   H. Deng, T. Vetrik, S. Balachandran, On the harmonic index and diameter of unicyclic graphs, Mathematical Reports 22 (2020), 11–18.
44.   M. R. Alfuraidan, T. Vetrik, S. Balachandran, General multiplicative Zagreb indices of graphs with a small number of cycles, Symmetry 12 (2020), 514.
45.   T. Vetrik, General formula for degree-based topological indices of titania nanotubes, U.P.B. Scientific Bulletin, Series B 82, No. 4 (2020), 125–132.
46.   M. Masre, S. A. Fufa, T. Vetrik, Distance-based indices of complete m-ary trees, Discrete Mathematics, Algorithms and Applications 12, No. 4 (2020), 2050041.
47.   J. P. Mazorodze, S. Mukwembi, T. Vetrik, Gutman index, edge-Wiener index and edge-connectivity, Transactions on Combinatorics 9, No. 4 (2020), 231–242.
48.   T. Vetrik, Degree-based topological indices of TUC4C8(S) nanotubes, U.P.B. Scientific Bulletin, Series B 81, No. 4 (2019), 187–196.
49.   M. S. Bataineh, M. M. M. Jaradat, T. Vetrik, Edge-maximal graphs without disjoint odd cycles, Ars Combinatoria 143 (2019), 247–253.
50.   D. A. Mengesha, T. Vetrik, Resolving sets of directed Cayley graphs for the direct product of cyclic groups, Czechoslovak Mathematical Journal 69, No. 3 (2019), 621–636.
51.   T. Vetrik, S. Balachandran, General multiplicative Zagreb indices of graphs with given clique number, Opuscula Mathematica 39, No. 3 (2019), 433–446.
52.   L. du Toit, T. Vetrik, On the metric dimension of circulant graphs with 2 generators, Kragujevac Journal of Mathematics 43, No. 1 (2019), 49–58.
53.   T. Vetrik, Polynomials of degree-based topological indices for hexagonal nanotubes, U.P.B. Scientific Bulletin, Series B 81, No. 1 (2019), 109–120.
54.   T. Vetrik, S. Balachandran, General multiplicative Zagreb indices of trees, Discrete Applied Mathematics 247 (2018), 341–351.
55.   P. Ali, P. Dankelmann, M. J. Morgan, S. Mukwembi, H. Swart, T. Vetrik, The average eccentricity, spanning trees of plane graphs, size and order, Utilitas Mathematica 107 (2018), 37–49.
56.   E. Maritz, T. Vetrik, The partition dimension of circulant graphs, Quaestiones Mathematicae 41, No. 1 (2018), 49–63.
57.   T. Vetrik, On bipartite Cayley graphs of small diameter, Mathematical Reports 20, No. 70 (2018), 171–176.
58.   T. Vetrik, Degree-based topological indices of hexagonal nanotubes, Journal of Applied Mathematics and Computing 58, No. 1 (2018), 111–124.
59.   T. Vetrik, The Randic index and the redefined Zagreb index of titania nanotubes TiO2 [m,n], U.P.B. Scientific Bulletin, Series B 80, No. 1 (2018), 157–162.
60.   M. M. M. Jaradat, M. S. Bataineh, T. Vetrik, A. M. M. Rabaiah, A note on the Ramsey numbers for theta graphs versus the wheel of order 5, AKCE International Journal of Graphs and Combinatorics 15, No. 2 (2018), 187–189.
61.   M. S. Bataineh, T. Vetrik, M. M. M. Jaradat, A. M. M. Rabaiah, The Ramsey number for two graphs of order 5, Journal of Discrete Mathematical Sciences and Cryptography 21 (2018), 1523–1528.
62.   M. Abas, T. Vetrik, Large Cayley digraphs and bipartite Cayley digraphs of odd diameter, Discrete Mathematics 340 (2017), 1162–1171.
63.   P. Mafuta, S. Mukwembi, S. Munyira, T. Vetrik, Hamiltonicity, minimum degree and leaf number, Acta Mathematica Hungarica 152 (2017), 217–226.
64.   T. Vetrik, On the metric dimension of circulant graphs with 4 generators, Contributions to Discrete Mathematics 12 (2017), 104–114.
65.   P. Dankelmann, E. Jonck, T. Vetrik, The degree-diameter problem for outerplanar graphs, Discussiones Mathematicae Graph Theory 37 (2017), 823–834.
66.   T. Vetrik, The metric dimension of circulant graphs, Canadian Mathematical Bulletin 60 (2017), 206–216.
67.   S. Dorfling, E. C. M. Maritz, J. Smit, T. Vetrik, Non-proper edge-colouring of graphs and hereditary graph properties, Quaestiones Mathematicae 40 (2017), 539–551.
68.   T. Vetrik, A. Ahmad, Computing the metric dimension of the categorial product of some graphs, International Journal of Computer Mathematics 94 (2017), 363–371.
69.   P. Ali, J. P. Mazorodze, S. Mukwembi, T. Vetrik, On size, order, diameter and edge-connectivity of graphs, Acta Mathematica Hungarica 152 (2017), 11–24.
70.   J. P. Mazorodze, S. Mukwembi, T. Vetrik, The Gutman index and the edge-Wiener index of graphs with given vertex-connectivity, Discussiones Mathematicae Graph Theory 36 (2016), 867–876.
71.   S. Dorfling, T. Vetrik, Edge-colouring of graphs and hereditary graph properties, Czechoslovak Mathematical Journal 66 (2016), 87–99.
72.   S. Mukwembi, T. Vetrik, On the radius of neighborhood graphs, Quaestiones Mathematicae 39 (2016), 577–585.
73.   T. Vetrik, Diameter of neighborhood graphs, Bulletin of the Malaysian Mathematical Sciences Society 39 (2016), 117–122.
74.   J. P. Mazorodze, S. Mukwembi, T. Vetrik, On the Gutman index and minimum degree, Discrete Applied Mathematics 173 (2014), 77–82.  
75.   P. Dankelmann, T. Vetrik, The degree-diameter problem for claw-free graphs and hypergraphs, Journal of Graph Theory 75 (2014), 105–123.
76.   T. Vetrik, Abelian Cayley graphs of given degree and diameter 2 and 3, Graphs and Combinatorics 30 (2014), 1587–1591.
77.   I. Broere, T. Vetrik, Universal graphs for two graph properties, Ars Combinatoria 116 (2014), 257–262.
78.   S. Mukwembi, T. Vetrik, Wiener index of trees of given order and diameter at most 6, Bulletin of the Australian Mathematical Society 89 (2014), 379–396.
79.   T. Vetrik, Cayley graphs of given degree and diameters 3, 4 and 5, Discrete Mathematics 313 (2013), 213–216.
80.   T. Vetrik, Large Cayley digraphs of given degree and diameter, Discrete Mathematics 312 (2012), 472–475.
81.   T. Vetrik, List coloring of complete multipartite graphs, Discussiones Mathematicae Graph Theory 32 (2012), 31–37.
82.   T. Vetrik, R. Simanjuntak, E. Baskoro, Large bipartite Cayley graphs of given degree and diameter, Discrete Mathematics 311 (2011), 324–326.
83.   H. Macbeth, J. Siagiova, J. Siran, T. Vetrik, Large Cayley graphs and vertex-transitive non-Cayley graphs of given degree and diameter, Journal of Graph Theory 64, No. 2 (2010), 87–98.
84.   T. Vetrik, L. Yulianti, E. Baskoro, On Ramsey (K1,2, C4)-minimal graphs, Discussiones Mathematicae Graph Theory 30 (2010), 637–649.
85.   T. Vetrik, An upper bound for graphs of diameter 3 and given degree obtained as Abelian lifts of dipoles, Discussiones Mathematicae Graph Theory 28 (2008), 91–96.
86.   E. Baskoro, T. Vetrik, L. Yulianti, A note on Ramsey (K1,2, C4)-minimal graphs of diameter 2, International Conference 70 Years of FCE STU (2008), 1–4.
87.   J. Siagiova, T. Vetrik, Large vertex-transitive and Cayley graphs with given degree and diameter, Electronic Notes in Discrete Mathematics 28 (2007), 365–369.
88.   T. Vetrik, Factorization of complete graphs into three factors with the smallest diameter equal to 3 or 4, Australasian Journal of Combinatorics 39 (2007), 183–190.
89.   T. Vetrik, Diameter in walk graphs, Acta Mathematica Universitatis Comenianae 76 (2007), 223–230.
90.   T. Vetrik, A note on factorization of complete graphs, Journal of Electrical Engineering 57 (2006), 99–100.
91.   T. Vetrik, Decompositions of complete graphs into three factors, Journal of Electrical Engineering 56 (2005), 113–114.

Conference presentations:

Keynote/invited speaker:

1.     T. Vetrik, General indices of graphs, 6th International Conference on Pure and Applied Mathematics, Sargodha, Pakistan, 6-7 December 2023 (keynote lecture, presented online).
2.     T. Vetrik, General distance-based indices of graphs, 2nd International Conference on Recent Advances in Mathematics, Lahore, Pakistan, 4-5 December 2023 (keynote lecture, presented online).
3.     T. Vetrik, The metric dimension of graphs, 7th UMT International Conference on Pure and Applied Mathematics, Lahore, Pakistan, 4-5 December 2023 (keynote lecture, presented online).
4.     T. Vetrik, General distance-based indices of graphs, 8th International Conference on Combinatorics, Cryptography, Computer Science and Computation, Tehran, Iran, 15–16 November 2023 (keynote lecture, presented online).
5.     T. Vetrik, General indices of graphs, International Conference on Graph Theory and Information Security V, Bandung, Indonesia, 22–25 May 2022 (invited lecture, presented online).
6.     T. Vetrik, Graphs of given degree and diameter, International Conference on Discrete Mathematics and Data Sciences ICDMDS‘18, Thanjavur, India, 28–29 September, 2018 (keynote lecture, presented online).
7.     T. Vetrik, Selected topics in the extremal graph theory, 13th Mathematical Conference in Nitra, Nitra, Slovakia, 18–19 June, 2015 (invited lecture).

Regular speaker:

1.     T. Vetrik, S. Balachandran, General multiplicative Zagreb indices of trees, 41st Australasian Conference on Combinatorial Mathematics and Combinatorial Computing, Rotorua, New Zealand, 10–14 December 2018
2.     T. Vetrik, The metric dimension and the partition dimension of circulant graphs, 8th International Conference on Research and Education in Mathematics, Bandung, Indonesia, 11–13 August 2017.
3.     M. Abas, T. Vetrik, Directed Cayley graphs of given degree and diameter, The Second Gdansk Workshop on Graph Theory, Gdansk, Poland, 26–28 June 2014.
4.     T. Vetrik, K-bases of groups and Cayley graphs, South African Mathematical Society. 56th Annual Congress, Pietermaritzburg, South Africa, 30 October – 1 November 2013.
5.     T. Vetrik, Large Cayley graphs of given degree and diameter 3, 4 and 5, South African Mathematical Society. 55th Annual Congress, Stellenbosch, South Africa, 30 October – 2 November 2012.
6.     T. Vetrik, P. Dankelmann, D. Erwin, S. Mukwembi, Inverse degree of a graph of given order and size, Joint Congress of the South African and American Mathematical Societies, Port Elizabeth, South Africa, 29 November – 3 December 2011.
7.     T. Vetrik, P. Dankelmann, The degree-diameter problem for claw-free graphs and hypergraphs, 23rd British Combinatorial Conference, Exeter, Great Britain, 3–8 July 2011.
8.     T. Vetrik, P. Dankelmann, Large claw-free graphs of given degree and diameter, South African Mathematical Society. 53rd Annual Congress, Pretoria, South Africa, 3–5 November 2010.
9.     T. Vetrik, E. Baskoro, L. Yulianti, A note on Ramsey (K1,2, C4)-minimal graphs of diameter 2, International Conference 70 Years of FCE STU, Bratislava, Slovakia, 4–5 December 2008.
10.   T. Vetrik, Large Cayley graphs of given degree and diameter, Konferensi Nasional Matematika XIV, Palembang, Indonesia, 24–27 July 2008.
11.   T. Vetrik, Choosability of complete multipartite graphs, 42nd Czech-Slovak Conference on Graph Theory, Hradec nad Moravicí, Czech Republic, 11–15 June 2007.
12.   T. Vetrik, Large vertex-transitive and Cayley graphs with given degree and diameter, 6th Czech-Slovak International Symposium on Combinatorics, Graph Theory, Algorithms and Applications, Prague, Czech Republic, 10–15 July 2006.
13.   T. Vetrik, Factorization of complete graphs, International Student Conference on Applied Mathematics – ISCAM 2006, Bratislava, Slovakia, 7–8 April 2006.
14.   T. Vetrik, Decompositions of graphs, 40th Czech-Slovak Conference on Graph Theory, Budmerice, Slovakia, 30 May – 3 June 2005.
15.   T. Vetrik, Decompositions of complete graphs, International Student Conference on Applied Mathematics – ISCAM 2005, Bratislava, Slovakia, 15–16 April 2005.

Short courses:

June 2023
Mongolian National University of Education, Ulaanbaatar, Mongolia
Extremal graph theory: one week long CIMPA course (12 hours) for PhD students, Master’s students and lecturers.

November 2022
COMSATS University Islamabad, Lahore Campus, Lahore, Pakistan
Cayley graphs and the degree-diameter problem: course for PhD students, Master’s students and lecturers (4 hours). Part of CIMPA School on Recent Advance in Combinatorics and its Applications.

January – February 2019
Adama Science and Technology University, Adama, Ethiopia
Algebraic graph theory: two weeks long course (28 hours) for PhD students.

October 2018
Addis Ababa University, Addis Ababa, Ethiopia
Coding theory: course for PhD students of the Addis Ababa University and the Adama Science and Technology University.

August 2017
Bandung Institute of Technology, Bandung, Indonesia
Algebraic graph theory: I helped with the course for about 20 postgraduate students. I taught a part of the course (2 weeks, 6 hours).

June 2016
Costa Rica Institute of Technology, Cartago, Costa Rica
Graph theory: two weeks long course for students and lecturers.

June 2015
University of the Philippines Baguio, Baguio, Philippines
Graph theory: two weeks long course (15 hours) for about 30 postgraduate students and lecturers from 5 universities in the Philippines.

First semester 2018-2021, 2024:
Discrete Mathematics: course for third year students, 
University of the Free State, Bloemfontein, South Africa

Second semester 2014, 2015, 2017-2019, first semester 2021-2023:
Coding Theory: course for postgraduate students, 
University of the Free State, Bloemfontein, South Africa

First semester 2014 and 2017: 
Graph Theory: course for postgraduate students, 
University of the Free State, Bloemfontein, South Africa

Second semester 2013: 
Calculus II: course for first year engineering students, 
University of Pretoria, Pretoria, South Africa

First semester 2013 and 2014: 
Mathematics I: course for first year science students, 
University of Pretoria, Pretoria, South Africa

First semester 2012: 
Mathematics for the Natural Science: course for first year students, 
University of KwaZulu-Natal, Durban, South Africa

First semester 2011: 
Linear Algebra and Coding Theory: course for third year science students, 
University of KwaZulu-Natal, Durban, South Africa

Second semester 2007 and 2008: 
Mathematics III: course for second year students of the Faculty of Civil Engineering, 
Slovak University of Technology, Bratislava, Slovakia

Second semester 2007 and 2008, first semester 2008: 
Mathematics I: course for first year students of the Faculty of Civil Engineering, 
Slovak University of Technology, Bratislava, Slovakia

First semester 2008: 
Mathematics II: course for first year students of the Faculty of Civil Engineering, 
Slovak University of Technology, Bratislava, Slovakia

Second semester 2007: 
Mathematics I: course for first year students of the Faculty of Architecture, 
Slovak University of Technology, Bratislava, Slovakia

Second semester 2004 and 2005, first semester 2005: 
Tutoring courses for undergraduate students, 
Slovak University of Technology, Bratislava, Slovakia

Second semester 2004 and 2005, first semester 2005: 
Tutoring courses for undergraduate students, 
University of Trencin, Trencin, Slovakia

Reviewer for international journals:

1.     Acta Mathematica Hungarica
2.     Acta Mathematica Universitatis Comenianae
3.     Advances and Applications in Discrete Mathematics
4.     AIMS Mathematics
5.     AKCE International Journal of Graphs and Combinatorics
6.     Arabian Journal of Mathematics
7.     Ars Combinatoria
8.     Ars Mathematica Contemporanea
9.     Asian-European Journal of Mathematics
10.   Atoms
11.   Australasian Journal of Combinatorics
12.   Bulletin of the Australian Mathematical Society
13.   Canadian Mathematical Bulletin
14.   Chemometrics and Intelligent Laboratory
15.   Complexity
16.   Computational and Applied Mathematics
17.   Computer Modeling in Engineering and Sciences
18.   Discrete Applied Mathematics
19.   Discrete Dynamics in Nature and Society
20.   Discrete Mathematics
21.   Discrete Mathematics Letters
22.   Discussiones Mathematicae Graph Theory
23.   Electronic Journal of Graph Theory and Applications
24.   European Journal of Combinatorics
25.   Far East Journal of Mathematical Sciences
26.   Filomat
27.   Georgian Mathematical Journal
28.   International Journal of Computer Mathematics
29.   International Journal of Quantum Chemistry
30.   Iranian Journal of Mathematical Chemistry
31.   Journal of Chemistry
32.   Journal of Graph Theory
33.   Journal of Interconnection Networks
34.   Journal of Mathematical and Statistical Analysis
35.   Journal of Mathematics
36.   Journal of Science and Arts
37.   Journal of the Operational Research Society
38.   Le Matematiche
39.   Main Group Metal Chemistry
40.   Mathematical Problems in Engineering
41.   Mathematics
42.   Open Chemistry
43.   Open Journal of Discrete Applied Mathematics
44.   Open Physics
45.   Optoelectronics and Advanced Materials
46.   Opuscula Mathematica
47.   Palestine Journal of Mathematics
48.   Polycyclic Aromatic Compounds
49.   Punjab University Journal of Mathematics
50.   Quaestiones Mathematicae
51.   Symmetry
52.   Tamkang Journal of Mathematics
53.   The European Physical Journal Plus
54.   Theoretical Computer Science
55.   Transactions in Mathematical and Computational Sciences
56.   Transactions on Combinatorics
57.   TWMS Journal of Applied and Engineering Mathematics
58.   U.P.B. Scientific Bulletin
59.   Utilitas Mathematica

I presented seminar talks at the following universities: 

1.     King Mongkut’s University of Technology Thonburi, Bangkok, Thailand (August 2023: 2 talks)
2.     University of Central Punjab, Lahore, Pakistan (November 2022)
3.     African Institute for Mathematical Sciences, Cape Town, South Africa (December 2021: online lecture)
4.     Yeungnam University, Gyeongsan, South Korea (July 2019)
5.     King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia (November 2018: two talks, April 2017)
6.     United Arab Emirates University, Al Ain, United Arab Emirates (February 2018)
7.     Addis Ababa University, Addis Ababa, Ethiopia (October 2017)
8.     Bandung Institute of Technology, Bandung, Indonesia (August 2017, June 2008)
9.     University of the Free State, Bloemfontein, South Africa (February 2017)
10.   University of Dar es Salaam, Dar es Salaam, Tanzania (October 2016)
11.   University of Costa Rica, San Jose, Costa Rica (June 2016)
12.   Costa Rica Institute of Technology, Cartago, Costa Rica (June 2016)
13.   University of the Philippines, Baguio, Philippines (June 2015)
14.   Qatar University, Doha, Qatar (November 2014)
15.   Nelson Mandela Metropolitan University, Port Elizabeth, South Africa (April 2014)
16.   University of Pretoria, Pretoria, South Africa (September 2012)
17.   University of Zimbabwe, Harare, Zimbabwe (March 2012)
18.   University of Andalas, Padang, Indonesia (February 2012)
19.   University of Malaya, Kuala Lumpur, Malaysia (January 2012)
20.   University of KwaZulu-Natal, Durban, South Africa (September 2011, March 2011, September 2010, July 2010)
21.   Sepuluh Nopember Institute of Technology, Surabaya, Indonesia (August 2008)
22.   University of Brawijaya, Malang, Indonesia (August 2008)
23.   Airlangga University, Surabaya, Indonesia (August 2008)
24.   Comenius University, Bratislava, Slovakia (April 2008, October 2007)
25.   Vienna University of Technology, Vienna, Austria (April 2006)