Every reference with a DOI in the deposited reference list resolved to a known
work in Crossref or DataCite at the dated check, and none carried a publisher retraction,
withdrawal, or removal notice.
The 77 checked references that resolve
resolves10.1371/journal.pone.0050555Pedal Claw Curvature in Birds, Lizards and Mesozoic Dinosaurs – Complicated Categories and Compensating for Mass-Specific and Phylogenetic Control
resolves10.1016/j.crpv.2005.12.018Histological observations of Enantiornithine bone (Saurischia, Aves) from the Lower Cretaceous of Las Hoyas (Spain)
resolves10.1111/j.1469-7580.2006.00534.xInsight into the evolution of avian flight from a new clade of Early Cretaceous ornithurines from China and the morphology of <i>Yixianornis grabaui</i>
resolves10.1038/nature03150Definitive fossil evidence for the extant avian radiation in the Cretaceous
resolves10.1371/journal.pone.0022292Assessing Arboreal Adaptations of Bird Antecedents: Testing the Ecological Setting of the Origin of the Avian Flight Stroke
resolves10.1080/02724634.2012.693865A subadult specimen of the Early Cretaceous bird<i>Sapeornis chaoyangensis</i>and a taxonomic reassessment of sapeornithids
resolves10.1139/E06-007A second enantiornithean (Aves: Ornithothoraces) wing from the Early Cretaceous Xiagou Formation near Changma, Gansu Province, People's Republic of China
resolves10.1029/2004GL019790Timing of the Jiufotang Formation (Jehol Group) in Liaoning, northeastern China, and its implications
resolves10.1029/2005GC001083The<sup>40</sup>Ar/<sup>39</sup>Ar dating of the early Jehol Biota from Fengning, Hebei Province, northern China
resolves10.1007/s00114-003-0489-1New Early Cretaceous fossil from China documents a novel trophic specialization for Mesozoic birds
resolves10.1002/jmor.1089Avian furcula morphology may indicate relationships of flight requirements among birds
resolves10.1111/j.1096-3642.2010.00671.xA new, three-dimensionally preserved enantiornithine bird (Aves: Ornithothoraces) from Gansu Province, north-western China
resolves10.1007/s11434-008-0209-5On the horizon of Protopteryx and the early vertebrate fossil assemblages of the Jehol Biota
resolves10.5962/bhl.title.542Caroli Linnaei...Systema naturae per regna tria naturae :secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis
resolves10.1671/039.029.0210Anatomy of the Early Cretaceous bird <i>Rapaxavis pani</i>, a new species from Liaoning Province, China
resolves10.3853/j.0067-1975.62.2010.1540A reassessment of Sinornis santensis and Cathayornis yandica (Aves: Enantiornithes). In Proceedings of the VII International Meeting of the Society of Avian Paleontology and Evolution, ed. W.E. Boles and T.H. Worthy
resolves10.1073/pnas.1117727108Additional specimen of
<i>Microraptor</i>
provides unique evidence of dinosaurs preying on birds
resolves10.1080/02724634.2009.10010371Phylogenetic support for a specialized clade of Cretaceous enantiornithine birds with information from a new species
resolves10.1038/382442a0An Early Cretaceous bird from Spain and its implications for the evolution of avian flight
resolves10.1038/292051a0New subclass of birds from the Cretaceous of South America
resolves10.1017/S0016756807003871Large euenantiornithine birds from the Cretaceous of southern France, North America and Argentina
resolves10.4202/app.2009.0095A Second Cretaceous Ornithuromorph Bird from the Changma Basin, Gansu Province, Northwestern China
resolves10.1139/e04-055Description of a new enantiornithine bird from the Early Cretaceous of Hebei, northern China
resolves10.1007/BF02900473Early diversification of birds: Evidence from a new opposite bird
resolves10.1080/02724634.2012.714431Anatomy of the basal ornithuromorph bird<i>Archaeorhynchus spathula</i>from the Early Cretaceous of Liaoning, China
resolves10.1007/s00114-004-0570-4The origin and early evolution of birds: discoveries, disputes, and perspectives from fossil evidence
resolves10.1007/BF03184320Two new ornithurine birds from the Early Cretaceous of western Liaoning, China
resolves10.1139/e03-011Anatomy of the primitive bird <i>Sapeornis chaoyangensis </i>from the Early Cretaceous of Liaoning, China
resolves10.1073/pnas.0507106102Discovery of an ornithurine bird and its implication for Early Cretaceous avian radiation
resolves10.1139/e05-038Anatomy of the Early Cretaceous bird <i>Eoenantiornis buhleri</i> (Aves: Enantiornithes) from China
resolves10.1098/rspb.2009.0885A new Lower Cretaceous bird from China and tooth reduction in early avian evolution
The 22 references without a DOI — listed, not checked
no DOI — not checkedHandbook of Avian Anatomy: Nomina Anatomica Avium,
no DOI — not checkedcit0007
no DOI — not checkedcit0008
no DOI — not checkedChiappe, L. M. 1996. Late Cretaceous birds of southern South America: anatomy and systematics of Enantiornithes and Patagopteryx deferrariisi; pp. 203–244 in G. Arratia (ed.), Contributions of Southern South America to Vertebrate Paleontology, Münchner Geowissenschaftliche Abhandlungen, Reihe A, Geologie und Paläontologie 30. Verlag Dr. Friedrich Pfeil, Munich.
no DOI — not checkedMesozoic Birds: Above the Heads of Dinosaurs
no DOI — not checkedMesozoic Birds: Above the Heads of Dinosaurs
no DOI — not checkedcit0014
no DOI — not checkedcit0032
no DOI — not checkedcit0036
no DOI — not checkedcit0038
no DOI — not checkedcit0041
no DOI — not checkedcit0098
no DOI — not checkedO’Connor, J.K. 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces). Ph.D. dissertation, University of Southern California, Los Angeles, California, 600 pp.
no DOI — not checkedcit0053
no DOI — not checkedPapers in Avian Paleontology
no DOI — not checkedMesozoic Birds: Above the Heads of Dinosaurs
no DOI — not checkedcit0097
no DOI — not checkedThe Beginnings of Birds
no DOI — not checkedZhou, Z. 1999. Early evolution of birds and avian flight—evidence from Mesozoic fossils and modern birds. Ph.D. dissertation, University of Kansas, Lawrence, Kansas, 230 pp.
no DOI — not checkedMesozoic Birds: Above the Heads of Dinosaurs
no DOI — not checkedcit0090
no DOI — not checkedcit0096
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