Čančalova, S., T. Stafilov, R. Šajn, and J. Alijagić. “SPATIAL DISTRIBUTION OF CHEMICAL ELEMENTS IN SOIL FROM THE STRUMICA REGION, REPUBLIC OF MACEDONIA”. Geologica Macedonica, Vol. 31, no. 2, Dec. 2017, pp. 117-30, https://js.ugd.edu.mk/index.php/GEOLMAC/article/view/1954.