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:The contradiction between our results and those of Morrel may be explained by the fact that Morrel‚Äôs conception was based on studying neuronal plasticity in animal models and human tumorous epilepsies and not on the classic chronic human epilepsies e.g. HS-associated TLE.101
 In subprimate species, the mirror focus usually develops after some days to
 months.
Category: