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:Although FGF23 and FGF2 can both induce hypertrophic growth of cardiac myocytes, FGF23 does so primarily by stimulating PLCg/calcineurin/NFAT signaling, whereas FGF2 activates the Ras/MAPK signaling axis (Faul et al., 2011).
Category: