Zaiats , V., RybytskaО., J. Majewski, T. Marciniak, and M. Zaiats. “Methods of Fuzzy Sets Theory for Statistical Analysis of Mass Service Systems. ”. COMPUTER-INTEGRATED TECHNOLOGIES: EDUCATION, SCIENCE, PRODUCTION, no. 38, Mar. 2020, pp. 23-32, doi:10.36910/6775-2524-0560-2020-38-04.