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:It has been previously reported that the blockage of the replication machinery can lead to uncoupling of leading and lagging strand synthesis, resulting in the generation of ssDNA, which in turn will be occupied by RPA, an SSB (38, 39).
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