Kalckmann, Raul Edgard, and Celmira T. A. Frattini. “A Study of the Interpredation of Potassium in Soil Test of Rio Grande Do Sul”. Pesquisa Agropecuaria Brasileira 2, no. 1 (April 15, 2014): 263–267. Accessed July 8, 2026. https://apct.sede.embrapa.br/pab/article/view/17901.