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:The current distributions of the 1066 species of marine fish and invertebrates, representing the average pattern of relative abundance in recent decades (i.e. 1980–2000), were produced using an algorithm developed by the Sea Around Us Project (see Close et al. 2006; Cheung et al. 2008a).
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