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:Mitochondrial division is a complex process that is essential for survival in mammals (Nunnari and Suomalainen, 2012; Archer, 2014) and is facilitated by the actin cytoskeleton (De Vos et al., 2005; DuBoff et al., 2012; Korobova et al., 2013, 2014; Hatch et al., 2014; Li et al., 2015).
Category: