Madalena, Fernando Enrique, et al. “Milk Yield and Calving Intervals of Holstein-Friesian and Crossbred Holstein-Friesian: Gir Cows in a High Management Level”. Pesquisa Agropecuaria Brasileira, vol. 18, no. 2, Apr. 2014, pp. 195-00, doi:10.1590/S1678-3921.pab1983.v18.15183.