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:For example, in the liver, pancreas, lung, and intestine, Sox9-positive cells can generate new daughter cells and differentiate into functional cells in damaged organs (Antoniou et al., 2009; Reginensi et al., 2011; Seymour et al., 2007; Turcatel et al., 2013; Vidal et al., 2005).
Category: