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:…Lagoon, Papua New Guinea, groups of the clown anemonefish, A. percula, are confined to sea anemones (Heteractis magnifica) that provide the fish with food, oviposition sites, and protection from predators (Mariscal 1970; Fautin 1992; Elliott et al. 1995; Elliott and Mariscal 2001; Buston 2003a).
Category: