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:Vol. 17, No. 4, December, 2013
translocation of these enzymes to the plasma membrane and/or other membrane (Littler et al., 2006; CorbalánGarcía & Gómez-Fernández, 2010).
Category: