How old are fossils? / by Sharat K. Roy, Asst. Curator of Invertebrate Paleontology.

no.9(1927)

Catalogue of type specimens in the Walker Museum of Paleontology and Chicago Natural History Museum: Radiolaria and Eurypterida / Matthew H. Nitecki, Walker Museum of Paleontology, University of Chicago. [Edited by Lillian A. Ross]

v.13:no.3(1963)