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:Many techniques for bone defatting are described in the literature, including mechanical cleaning with water or air jet,(8) acetone ⁄ ethanol solution,(9) enzyme detergents,(8) hydrogen peroxide,(11) aqueous sodium hydroxide,(12) and sodium hypochlorite (NaOCl).(8,13) We adopted the latter technique, because it has been found suitable for formalinized specimens,(7) is safe for personnel and is very low cost.
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