New records of Sphenopteris from the Cisuralian of Yongchang,Gansu Province,with a discussion on diversity and palaeogeographic evolution of this genus during the Late Paleozoic
WANG Xuelian, XIONG Conghui, SUN Bainian
JOPC . 2023, (2): 471 -484 .  DOI: 10.7605/gdlxb.2023.02.029