Ordinal judgments of symbolic stimuli by capuchin monkeys (Cebus apella) and rhesus monkeys (Macaca mulatta): The effects of differential and nondifferential reward

Journal of Comparative Psychology (2008) - Comment
doi: 10.1037/0735-7036.122.1.52 issn: 1939-2087 issn: 0735-7036 pubmed: 18298281

Michael J. Beran, Emily H. Harris, Theodore A. Evans, Emily D. Klein, Betty Chan, Timothy M. Flemming, David A. Washburn