M. R. . Ventura-Lucas, C. . Marques, M. . de Belém Martins, and R. . Fragoso, “Portuguese agriculture and its role in multifunctional rural development”, APSTRACT, vol. 4, no. 5-6, pp. 145–152, Dec. 2010, doi: 10.19041/APSTRACT/2010/5-6/23.