JGSL
The Winneshiek biota: exceptionally well-preserved fossils in a Middle Ordovician impact crater
Derek E.G. Briggs, Huaibao P. Liu, Robert M. McKay and Brian J. Witzke
Journal of the Geological Society, 175, 865-874, 24 September 2018, https://doi.org/10.1144/jgs2018-101
Cannot recommend this one highly enough
size:about 8,5 MB
Note:the Ames impact straddles the Arbuckle/Simpson Boundary