Gomes, Cezesmundo Ferreira, et al. “AVAILABILITY OF SILICON FOR RICE CROP ACCORDING TO SOURCES, INCUBATION TIME, AND SOIL CLASSES”. Pesquisa Agropecuária Tropical [Agricultural Research in the Tropics], vol. 41, no. 4, Dec. 2011, pp. 531-8, https://doi.org/10.5216/pat.v41i4.10906.