STOYANOVA , V.; KOTSEV, T. .; ZHELEZOV, G. .; SIMA , M. .; LEVEI, E.-A. . Copper concentration in the soils of the Danube floodplain between the rivers Timok and Vit northwestern Bulgaria. European Journal of Geography, [S. l.], v. 10, n. 2, 2019. Disponível em: https://www.eurogeojournal.eu/index.php/egj/article/view/182. Acesso em: 14 jun. 2025.