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:Interestingly, actin assembly was also recently revealed to take place at the interior of forming autophagosomes, and to be dependent on the phospholipid phosphatidylinositol 3-phosphate (PI(3)P; Mi et al., 2015).
Category: