Condra, Geo. E. 1869-1958. The Middle River traverse of Iowa, by G. E. Condra and J. E. Upp. - [Lincoln] Printed by authority of the state of Nebraska, 1933. - 31 p. Bibliographical foot-notes. LCCN: gs 34000114 Subjects--Topical Terms: Geology--Iowa. LC Class. No.: QE135 / .A43 no. 4