Monkeys learn to do arithmetic for peanuts. New Scientist, August 15, 2007

Token values. Current Biology, 17:R737, September 4, 2007

Monkeys understand money. Nature, Published online June 11, 2008

Animal behaviour: Token symbolism. Nature, 453:960, June 19, 2008

Scambio di figurine tra cebi. Galileo, June 11, 2008

Le scimmie con il senso degli affari. Repubblica, June 12, 2008

Almonds or pizza? Capuchins are even smarter than we thought. Wellsphere, June 2, 2009

Monkeys choose variety for variety's sake. Science Daily, March 16, 2010