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:According to Hale et al. (2000), the presence of the LINE-1 element is part of the “taurine” haplotype of the GHR gene; no such sequence was found in Zebu cattle (Bos indicus).
Category: