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:These results are in keeping with previous research investigating the processing of kana and alphabetic languages (Bolger et al., 2005; Ischebeck et al., 2004; Nakamura et al., 2005; Sakurai et al., 1993, 2000; Tan et al., 2005a; Thuy et al., 2004), as well as kanji and logographic languages…
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