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:Milk fat globule-EGF-factor (MFGE8), also named lactadherin, PAS 6/7, SED1, BA46, p47, is a secreted glycoprotein first described in milk fat globules released in milk by mammary epithelial cells [1,2].
Category: