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:Deep pocket volumes of surface pockets at protein interaction sites harboring a bound inhibitor (red circles) and pockets found elsewhere on the protein surface (black x’s) are plotted against the corresponding pocket volumes identified by Q-SiteFinder, for each of the sites used in Figure 1B.
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