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:Based on the definitions of the OISR tuple elements, we introduce an evaluation framework, which is a specialisation of the BWW evaluation framework [15,16] that is aimed at assessing the expressive power of modelling methods to be applied for OISR representation.
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