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:On the other hand, some researchers (e.g., Lister, 1990; Ramos & Mormède, 1998) have questioned the use of ambulation and defecation as indexes of emotionality in the first place.
Category: