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:monly seen in men and caused by different fungi, including Madurella mycetomatis, especially frequent in Africa; Madurella grisea, common in South America; and Pseudallescheria boydii (Scedosporium apiospermum), more frequently seen in the USA, but also reported in Europe [48, 49].
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