Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:Species living solitary or in dispersed groups are assumed to exhibit polygynandrous mating systems (e.g. Kappeler 1997b; Eberle and Kappeler 2002; Radespiel et al. 2002) and were thus lumped in one category with species living in cohesive groups.
Category: