Dias, Waldir Pereira, et al. “Bootstrap Confidence Intervals As Tool to Classify Races of soybean’s Cyst Nematode”. Pesquisa Agropecuaria Brasileira, vol. 35, no. 2, Feb. 2000, pp. 271-5, doi:10.1590/S1678-3921.pab2000.v35.5766.