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:, 1997), have focused on representing specific tasks and domains, the attention has shifted to more general purpose schemas such as the Dialogue Act Markup using Several Layers (DAMSL) (Allen, 1997) and the ISO 24617-2(Bunt et al., 2010; Bunt et al., 2012), a standard for dialog act annotation.
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