Van Leeuwen, Edwin J. C. Comparative Cognitive Anthropology, MPI for Psycholinguistics, Max Planck Society;
Van Leeuwen, E. J. C. (2012). Grooming hand-clasping in chimpanzees: Social culture?. Talk presented at the 6th European Conference on Behavioural Biology. Essen, Germany. 2012-07-19 - 2012-07-22.