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:Approximately 45% of the predicted proteome of Leptospirillum Group II, the numerically dominant organism in floating AMD biofilms (Tyson et al., 2004; Denef et al., 2010b), was identified.
Category: