Early and Middle Ordovician chitinozoans from Tongzi, South China : biostratigraphic significance and biodiversificationLiang, Yan; Tang, Peng; Zhan, Renbin; Hints, Olle10th Baltic Stratigraphic Conference : Checiny, 12-14 September 2017 : abstracts and field guide2017 / p. 48-49 : ill http://geo.uw.edu.pl/tl_files/publikacje/10th_Baltic_Stratigraphic_Conference_Abstracts_and_Field_Guide.pdf