TROIANO, STEFANIA, and FRANCESCO MARANGON. 2011. “I Payments for Ecosystem Services a Pro Dal Paisaç E Dal Ambient”. Gjornâl Furlan Des Siencis - Friulian Journal of Science 15 (15). Udine, Italy:59-67. https://www.gfs-fjs.net/index.php/gsf/article/view/158.