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:b-catenin normally associates with E-cadherin and with a-catenin and thereby participates in the regulation of cell-to-cell adhesion (Vleminckx and Kemler 1999; Miyoshi and Takai 2005).
Category: