Iowa Fisheries Research Technical Series No. 75-1 Variations in the abundance of channel catfish year classes in the upper Mississippi River and causative factors Don R. Helms, Fishery Research Biologist Fisheries Section Jerry M. Conley, Superintendent of Fisheries December, 1975

study of channel catfish in the Mississippi River to determine differences in year class abundance and causative factors

The impact of restricting beverage container use in Iowa, 1/1/77.

Suzan M. Stewart, Research Librarian, Iowa Geological Survey. and Edward J. Stanek II, Director, Air Management Division, Iowa Department of Environmental Quality