BIALI, G. “MONITORING THE EFFECTS OF EXCESSIVE USE OF CHEMICAL FERTILIZERS ON UNDERGROUND WATERS BY USING THE GIS TECHNIQUE”. Studia Universitatis Babeș-Bolyai Geographia, vol. 61, no. 2, Sept. 2016, pp. 73-84, http://193.231.18.162/index.php/subbgeographia/article/view/5649.