Yokoo, Marcos Jun Iti, et al. “Genetic Correlations Between Visual Scores and Carcass Traits Measured by Real-Time Ultrasound in Beef Cattle”. Pesquisa Agropecuaria Brasileira, vol. 44, no. 2, Nov. 2010, pp. 197-02, doi:10.1590/S1678-3921.pab2009.v44.1438.