An early Oligocene fossil acorn, associated leaves and pollen of the ring‐cupped oaks (Quercus subg. Cyclobalanopsis) from Maoming Basin, South China
Xiao-Yan Liu, Sheng-Lan Xu, Meng Han, and Jian-Hua Jin
J Syst Evol . 2019, (2): 153 -168 .  DOI: 10.1111/jse.12450