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:Four items measured anthropomorphism, defined as attributing
humanlike mental capacities of agency and experience to it (Epley et al., 2007; Gray et al., 2007; Waytz et al., 2010).
Category: