CORDEIRO, ALEXANDRA FERREIRA DA SILVA, et al. “PIG (SUS SCROFA) VOCALIZATION ASSESSMENT AS AN INDICATOR OF ENERGY EXPENDITURE”. Revista Brasileira De Engenharia De Biossistemas, vol. 2, no. 2, Nov. 2008, pp. 143-52, doi:10.18011/bioeng2008v2n2p143-152.