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:This result is in agreement with the findings that mouse embryos homozygous for a null goosecoid allele do not have gastrulation or neural induction defects (Yamada et al., 1995; Rivera-Perez et al., 1995) and chick embryos can develop normally even when manipulated so that their organizer does not express goosecoid(Psychoyos and Stern, 1996).
Category: