Gaurat, Jéssica Oliveira, et al. “Foliar Nutrient Contents and Yield Performance of Blackberry With Potassium Fertilization”. Pesquisa Agropecuaria Brasileira, vol. 55, no. X, Dec. 2020, p. e02198, doi:10.1590/S1678-3921.pab2020.v55.26850.