BURNY, Philippe, et al. “ORGANIC FARMING AND THE GREENING OF THE COMMON AGRICULTURAL POLICY MADE WALLOON AGRICULTURE BECOME MORE ENVIRONMENT FRIENDLY IN 2015”. Studia Universitatis Babeș-Bolyai Ambientum, vol. 61, no. 1-2, Dec. 2016, pp. 15-24, https://studia.reviste.ubbcluj.ro/index.php/subbambientum/article/view/4179.