Calabrese, J., C. Pacini, C. Vazzana, and M. Nikolla. “Sustainability Comparison Between Organic and Conventional Systems at Farm and Field Scale: A Case Study in Olive Production Systems in Apulia Region”. European Journal of Sustainable Development, vol. 2, no. 4, Apr. 2013, p. 19, doi:10.14207/ejsd.2013.v2n4p19.