A widely accepted identification feature of Steppe Eagle Aquila nipalensis is that the gape-line extends to a point level with, or even beyond, the rear edge of the eye (e.g. Cramp & Simmons 1980, Brown et al. 1982, Newman 1984, Porter et al. 1996, Beaman & Madge 1998, Svensson et al. 1999, Robson 2000, Ferguson-Lees & Christie 2001). In particular, this long gape-line is proffered as

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