| Reference | Heyl, A.V., Jr., Agnew, A.F., Lyons, E.J., And Behre, C.H., Jr., With Special Sections By Flint, A.E., 1959, The Geology Of The Upper Mississippi Valley Zinc-Lead District: U.S. Geological Survey Professional Paper 309, 310 P |
| Reporter | Hedgman, Cheryl (Cannon, W.), Sutphin, David M., Mason Jr., G.T., Eastern Field Operations Center (EFOC) |