RAKOVSKÁ, Eva - HUDEC, Miroslav. A Three-Level Aggregation Model for Evaluating Software Usability by Fuzzy Logic. - Registrovaný: Web of Science, Registrovaný: Scopus. In International Journal of Applied Mathematics and Computer Science. - Zielona Góra : University of Zielona Góra Press. ISSN 1641-876X, 2019, vol. 3, no. 29, pp. 489-501 online. VEGA 1/0373/18.