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:In contrast, the pro-hypertrophic effects of the prototypical paracrine FGF family member, FGF2, were blocked by inhibitors of the Ras/MAPK cascade (Faul et al., 2011).
Category: