Trilobites, Biostratigraphy, and Lithostratigraphy of the Crepicephalus and Aphelaspis zones, Lower Deadwood formation (Marjuman and Steptoean Stages, Upper Cambrian), Black Hills, South Dakota
J. H. Stitt, and
P.J. Perfetta
2000
Article
Journal of Paleontology
74(2):199-223
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