Ksepka, Daniel T.; Stidham, Thomas A.; Williamson, Thomas E. (25 Temmuz 2017). "Early Paleocene landbird supports rapid phylogenetic and morphological diversification of crown birds after the K–Pg mass extinction". Proceedings of the National Academy of Sciences. 114 (30). ss. 8047-8052. doi:10.1073/pnas.1700188114. PMC5544281 $2. PMID28696285.
Ksepka, Daniel T.; Stidham, Thomas A.; Williamson, Thomas E. (25 Temmuz 2017). "Early Paleocene landbird supports rapid phylogenetic and morphological diversification of crown birds after the K–Pg mass extinction". Proceedings of the National Academy of Sciences. 114 (30). ss. 8047-8052. doi:10.1073/pnas.1700188114. PMC5544281 $2. PMID28696285.