Andreev, Andrey, and Gergana Andreeva. “Modeling of the River System of Goliama Kamchia”. JOURNAL SCIENTIFIC AND APPLIED RESEARCH 2, no. 1 (March 4, 2023): 50–57. Accessed April 6, 2025. https://jsar.ftn.shu.bg/index.php/jsar/article/view/43.