Sinkholes, hydrogeology and ground-water quality in northeast Iowa /
George R. Hallberg, Bernard E. Hoyer.
APA Citation
Hallberg, G. R., Hoyer, B. E., Iowa. Department of Environmental Quality., Iowa Geological Survey. (1982). Sinkholes, hydrogeology and ground-water quality in northeast Iowa. Iowa City, Iowa: Iowa Geological Survey.
MLA Citation
Hallberg, George R, Bernard E Hoyer, Iowa. Department of Environmental Quality, and Iowa Geological Survey. Sinkholes, Hydrogeology And Ground-water Quality In Northeast Iowa. Iowa City, Iowa: Iowa Geological Survey, 1982.
Warning: These citations may not always be complete (especially for serials).