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 the dependability definition (see Section 2.4 below), the attribute safety, since it is also included in the dependability definitions seen in Section 1, is directly included in the definition (see (Rüdiger et al., 2007a) for a definition of the remaining attributes in a behavioral context).
Category: