Shopova, N., N. Tsaikin, and V. Alexandrov. “Study of the Trends in Honey Productivity and Honey Bee Mortality under Hydrothermal Conditions in Eastern Bulgaria During the Period 2008-2020”. Journal of BioScience and Biotechnology, vol. 11, no. 2, Jan. 2023, pp. 111-7, https://editorial.uni-plovdiv.bg/index.php/JBB/article/view/443.