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:…2009 The Authors Journal compilation © 2009 The Royal Entomological Society 257
attempt to reconstruct the evolutionary history of the S. damnosum complex using sequences of the nuclear ITS2 rDNA and the mitochondrial 16S gene resulted in inconsistent phylogenies (Krueger & Hennings, 2006).
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