Hangwula in Alashan League, Inner Mongolia (105.628, 38.757, Yuanbaoshan Formation)
Ge, M.Y., Zheng Z.C., Li, Y.Z. 1990. Research of Ordovician and Silurian graptolites and graptolite bearing strata from Ningxia and the neighbouring districts. Nanjing, Nanjing University Press, 1–190.