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:Additional studies have implicated Rab5A and 5C in microneme protein trafficking and rhoptry biogenesis [22], and homologues of dynamin and sortilin have also been identified as critical for the trafficking of some proteins [23,24].
Category: