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:In the late differentiation phases of somatotroph cells, GHRH activates Gs alpha, cAMP, and the protein kinase A pathway through its cell membrane receptor GHRH-R (1,10,11).
Category: