TY - JOUR A1 - Unwin, D. M. A1 - Lü, J. A1 - Bakhurina, N. N. T1 - On the systematic and stratigraphic significance of pterosaurs from the Lower Cretaceous Yixian Formation (Jehol Group) of Liaoning, China JO - Foss. Rec. J1 - FR VL - 3 IS - 1 SP - 181 EP - 206 Y1 - 2000/01/01 PB - Wiley SN - 2193-0074 UR - https://fr.copernicus.org/articles/3/181/2000/ L1 - https://fr.copernicus.org/articles/3/181/2000/fr-3-181-2000.pdf DO - 10.1002/mmng.20000030109 ER -