Time factors of differentially preserved wood in two calcitic concretions in Pennsylvanian black shale from Indiana / Bertram G. Woodland -- and Catherine K. Richardson --.

v.33:no.10(1975)

A new shark of the family Edestidae, Ornithoprion hertwigi, from the Pennsylvanian Mecca and Logan quarry shales of Indiana / Rainer Zangerl --

v.16:no.1(1966)