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:Some investigators have demonstrated only brainstem LBD using histochemical methods [43] while others have demonstrated limbic LBD [41], and still others neocortical LBD [54, 82] in cases of AD caused by mutations in APP.
Category: