Kliemann, H. J., and D. V. Lima. “AGRONOMIC EFFICIENCY OF NATURAL PHOSPHATES AND THEIR INFLUENCE ON SOIL AVAILABLE PHOSPHORUS ON TWO CERRADO SOILS”. Pesquisa Agropecuária Tropical [Agricultural Research in the Tropics], vol. 31, no. 2, Nov. 2007, pp. 111-9, https://revistas.ufg.br/pat/article/view/2472.