Schuppli, C., Meulman, E. J. M., Forss, S. I. F., Aprilinayati, F., van Noordwijk, M. A., & van Schaik, C. P. (2016).
Observational social learning and socially induced practice of routine skills in immature wild orang-utans.
Animal Behaviour, 119, 87-98. doi:10.1016/j.anbehav.2016.06.014.