Great Lakes levels /
US Army Corps of Engineers, North Central Division.
APA Citation
United States. Army. Corps of Engineers. North Central Division. (19901994). Great Lakes levels. [Chicago, Ill.?]: The Division.
MLA Citation
United States. Army. Corps of Engineers. North Central Division. Great Lakes Levels. [Chicago, Ill.?]: The Division, 19901994.
Warning: These citations may not always be complete (especially for serials).