Tan, A. W., Luncz, L., Haslam, M., Malaivijitnond, S., & Gumert, M. D. (2016). Complex processing of prickly pear cactus (Opuntia sp.) by free-ranging long-tailed macaques: preliminary analysis for hierarchical organisation. Primates, 57(2), https://doi.org/10.1007/s10329-016-0525-3