89
Brian Hare and Suzy Kwetuenda (2010), Jinghzi Tan and Hare (2013).
90
Victoria Horner et al. (2011).
91
Ernst Fehr et al. (2018).
92
Shinya Yamamoto, Tatyana Humle, and Masayuki Tanaka (2012).
93
Roger Fouts (1997).
94
Martin Hoffman (1981), p. 133.
95
Inbal Ben-Ami Bartal, Jean Decety, and Peggy Mason (2011).
96
Nobuya Sato et al. (2015).
97
Inbal Ben-Ami Bartal et al. (2016).
98
Felix Warneken and Michael Tomasello (2014).