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 key insight of the authors in [12] is that a memory access to a location which is private to a given thread can be successfully reordered with respect to a memory access to a location which is shared amongst multiple threads without violating SC; it is only for memory operations to shared data that ordering constraints need to be imposed.
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