, Constanta, Romania, 2005.
 San Skulrattanakulchai. Acyclic colorings of subcubic graphs. Information processing letters, 92(4):161_167, 2004.
 P.G. Tait. On the coloring of maps. Proc. Royal Soc. Edinburgh, 10:501_503, 1880.
 A. Vince. Star chromatic number. Journal of Graph Theory, 12(4):551_559, 1988.
 V.G. Vizing. On an estimate of the chromatic class of a p-graph. Diskret. Analiz., 3:24_30, 1964.
 R.J.Waters. Graph Colouring and Frequency Assignment. PhD thesis
Vita Graudina, Janis Grundspenkis and Sigita Milasevica
Adaptive Knowledge Assessment System: Implementation and Evaluation Results. In Scientific Proceedings of Riga Technical University, 5th Series, Computer Science. Applied Computer Systems, Vol. 38, 2009, pp. 13-24.
 Vilkelis M., Anohina A., Lukashenko R. Architecture and Working Principles of the Concept Map Based Knowledge Assessment System. In Proceedings of the 3rd International Conference on Virtual Learning (ICVL 2008), October 31 - November 2, 2008, Constanta, Romania, pp. 81-90.
 Ehrig M. Ontology Alignment: Bringing the
Romans Lukasenko, Alla Anohina-Naumeca, Marks Vilkelis and Janis Grundspenkis
the Use of Concept Mapping Techniques and Technologies for Education and Performance Support , Technical report, FL, 2003.
M. Vilkelis, A. Anohina, and R. Lukashenko, "Architecture and working principles of the concept map based knowledge assessment system," in The 3rd International Conference on Virtual Learning , October 31-November 2, 2008. Romania: University of Constanta, 2008, pp. 81-90.
J. Grundspenkis and M. Strautmane, "Usage of graph patterns for knowledge assessment based on concept maps," in The 49th
Olegas Vasilecas, Evaldas Laureckas and Audrius Rima
expressiveness,” in Romanian- Austrian Workshop on Computer-Aided Verification of Information Systems, 2004, pp. 20-22.
 R. M. Dijkman, M. Dumas, and C. Ouyang, “Semantics and analysis of business process models in BPMN,” Information and Software Technology, vol. 50, no. 12, pp. 1281-1294, 2008. http://dx.doi.org/10.1016/j.infsof.2008.02.006
 T. Dufresne and J. Martin, “Process modeling for e-business,” Information Systems Department, George Mason University, 2003.
 L. J. Enstone and M. F. Clark, “BPMN and simulation