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:These include the HGMD (Stenson et al. 2009), the NHGRI Catalog of Published GWAS (Hindorff et al. 2001) and the OMIM (Amberger et al. 2009).
Category: