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 this scenario, actin filament polymerization within the gap between the ER tubule surrounding the mitochondria and the mitochondrial outer membrane (Figure 8A) results in localized pressure that drives mitochondrial constriction to diameters required for Drp1 helix formation (Korobova et al., 2013).
Category: