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:Unfortunately, despite all the extensive work conducted worldwide through basic In Vitro method[6-8], In Silico information[9-10], hybrid method[11], mimicking the In Vivo test as far as possible[12-13].
Category: