↑Chiappe, Luis M. (2007). Glorified Dinosaurs: The Origin and Early Evolution of Birds. University of New South Wales Press, Sydney. ISBN 978-0-86840-413-4.
↑Lee, Michael SY; Cau, Andrea; Darren, Naish; Gareth J., Dyke (2013). «Morphological Clocks in Paleontology, and a Mid-Cretaceous Origin of Crown Aves». Systematic Biology. Oxford Journals. 63 (3): 442–9. PMID24449041. doi:10.1093/sysbio/syt110.
↑Lee, Michael SY; Cau, Andrea; Darren, Naish; Gareth J., Dyke (2013). «Morphological Clocks in Paleontology, and a Mid-Cretaceous Origin of Crown Aves». Systematic biology. Oxford Journals. doi:10.1093/sysbio/syt110.