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Marek Szajt
Ph.D., Associate ProfessorCzestochowa University of Technology Faculty of Management Department of Econometrics and Statistics Armii Krajowej 19 B, 42-200Częstochowa, Poland
Marcin Zawada
Ph.D., Eng. Czestochowa University of Technology Faculty of Management Department of Econometrics and Statistics Armii Krajowej 19 B, 42-200Częstochowa, Poland