Maxillae are drawn from photos by P.S. of AMNH (American Museum of Natural History, New York City, New York) FR 6515 (Velociraptor), IVPP V 12615 (Sinovenator), IVPP V 11527 (Sinusonasus), CEUM 7319 (Geminiraptor), IGM (Mongolian Institute of Geology, Ulaan Baatar, Mongolia) 100/983 (Byronosaurus), AMNH FR 6516 (Saurornithoides), and IGM 100/1 (Zanabazar); and reference 18 (Archaeopteryx).
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