8[4]Ronald R,Swaisgood,Angela M,White,Xiaoping Zhou,et al.A quantitative assessment of the efficacy of an environmental enrichment programme for giant pandas[J].Animal Behaviour,2001,61:447～457.
9[6]Mason GJ.Stereotypies and suffering[J].Behavioral Processes,1991,25:103～115.
10[7]Liu Dingzhen,et al.Behavior of giant pandas in captive conditions:Gender differences and enclosure effects[J].Zoo Biology,2003,22(1):77～82.
