Original: Christopher Boehm (1999) "Hierarchy in the Forest: The Evolution of Egalitarian Behavior" page 198 Harvard university press Leften Stavros Stavrianos (1991).
Simplified: References Christopher Boehm (1999) "Hierarchy in the Forest: The Evolution of Egalitarian Behavior" page 198 Harvard university press Leften Stavros Stavrianos (1991).