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 particular, we show new findings on the following universal hash functions and MAC algorithms based thereupon: polynomial hash [6, 13, 8, 22, 25], MMH [17], Square Hash [15], NH/UMAC [9] and its variants VMAC [28] and WH/WMAC [23].
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