Espanhol, Gilmar Luiz, et al. “Soil Chemical and Physical Properties Modified by Weed Control and Organic Fertilization in an Apple Orchard”. Revista De Ciências Agroveterinárias, vol. 6, no. 2, Dec. 2007, pp. 83-94, https://periodicos.udesc.br/index.php/agroveterinaria/article/view/5368.