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:Note that the experiments in both our earlier LCFR paper (Joslin & Pollack, 1994) and Gerevini and
Schubert's (1996) ZLIFO paper were run using an earlier version (v.2) of UCPOP.
Category: