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:Frequent methylation for TIMP3 (Kang et al. 2006) and CDH13 (Suehiro et al. 2008) in the present study concurs with previously published results in endometrial cancer.
Category: