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:The results are supported by previous studies (Ranjit et al. 2010, Taliaferro et al. 2010, Pearson et al. 2009, Roos et al. 2001, √òverby & Andersen 2000).
Category: