Maluche-Baretta, C.R.D., Amarante, C.V.T. do and Klauberg Filho, O. (2006) “Multivariate analysis of soil attributes of apple orchards under conventional and organic production systems”, Pesquisa Agropecuaria Brasileira, 41(10), pp. 1531–1539. doi:10.1590/S1678-3921.pab2006.v41.7313.