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:…recent reports have implicated CHH as a regulator of multiple physiological effects, which include reproduction (De Kleijn and Van Herp, 1998; Khayat et al., 1998), molting (Chung et al., 1999), osmoregulation (Serrano et al., 2003; Spanings-Pierrot et al., 2000), and lipid metabolism…
Category: