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:Specifically, Step 1 implements the coordinated competition (Xu, 1998a), which has different simplified forms for specific qðxly; ‘Þ and qðy;‘Þ: For the case of Eq.
Category: