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 Bacillus strains secrete significantly large amounts of alkaline proteases with good stability at higher pH and temperature values, which can be considered as compatible additives in laundry detergents [5–7, 14, 16, 17, 20, 27].
Category: