Dunbar, R., Duncan, N., & Nettle, D. (1995). Size and structure of freely forming conversational groups. Walter de Gruyter, Inc. New York.

Dunbar, R., N. Duncan, and D. Nettle. Size and Structure of Freely Forming Conversational Groups. Walter de Gruyter, Inc. New York, 1995.

Dunbar, R., et al. Size and Structure of Freely Forming Conversational Groups. Walter de Gruyter, Inc. New York, 1995.