p Econ 9:79-101. 52. Restive M, van de Rip A (2012) Experimental study of informal rewards in peer priakidiOn. P105 One 7:e34358. 53. Lieberman E, Hauert C, Nowak MA (2005) Evolutionary dynamics on graphs. Nature 933:112-316. 54. Szab0 G, Path G (2007) Evolutionary games On graphs. PhYS Rep 946.97-216.