L. D. C. Laperuta et al., “New genes conferring resistance to Asian soybean rust: allelic testing for the Rpp2 and Rpp4 loci”, PAB, vol. 43, no. 12, pp. 1741–1747, Jan. 2009, doi: 10.1590/S1678-3921.pab2008.v43.1129.