Petrov, Kamen, Nikolay Tsonkov, and Krasimira Slaveva. “Regional Development Of Municipalities With A Population Of 10 To 30 Thousand In The North-Eastern And South-Eastern Planning Regions Of Bulgaria”. Journal of Ecohumanism 3, no. 8 (December 2, 2024): 3626–3640. Accessed December 22, 2024. https://ecohumanism.co.uk/joe/ecohumanism/article/view/5029.