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:Members of this family are present in animals from cnidarians to mammals and contain at least one cysteine-rich CABIT domain and a low-complexity proline-rich stretch (Chung et al., 2009; Johnson et al., 2009).
Category: