Author: Rexroad, C.B., 1957.:
Title: Conodonts from the Chester Series in the type area of Southwestern Illinois. [Rep. Invest. St. Geol. Surv., 199.]
Description: Urbana, Illinois. 8vo. Pp. 43, 96 microphotos on 4 plates, 21 figs. and sections in text, refs. Orig. wrappers.

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