Boyanov, Petar. “Content of Vol. 16, 2019, Journal Scientific and Applied Research: Content of Vol. 16, 2019, Journal Scientific and Applied Research”. JOURNAL SCIENTIFIC AND APPLIED RESEARCH 16, no. 1 (March 21, 2023). Accessed November 24, 2024. https://jsar.ftn.shu.bg/ojs-3.3.0-7/index.php/jsar/article/view/256.