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:For the linguistic feature extraction phase we wrapped several state-of-the-art NLP tools: Stanford CoreNLP12 for POS, NERC, TERN, and coreference resolution; mate-tools13 for DP and SRL, with mappings between frame resources from the Predicate Matrix [10]; DBpedia Spotlight14 for EL; and, UKB15 for WSD.
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