Laumer, I. B., Massen, J. J. M., Wakonig, B., Lorck-Tympner, M., Carminito, C., & Auersperg, A. M. I. (2020). Tentative evidence for inequity aversion to unequal work-effort but not to unequal reward distribution in Goffin's cockatoos. Ethology, 126(2), 185-194. doi:10.1111/eth.12947.