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:At the plateau margins, the fold fabric is commonly organized into long, wide, margin-parallel belts perpendicular to the trend of the pervasive extensional fabric [e.g., Bindschadler et al., 1992a, 1992b; Brown and Grimm, 1997; Gilmore et al., 1997, 1998; Ghent and Hansen, 1999].
Category: