1. Bouguer gravity anomaly map of the United States;Woollard;U.S. Geol. Surv. Spec. Map,1964
2. Correlation of gravity anomalies with the Keweenawan geology of Wisconsin and Minnesota;Thiel;Geol. Soc. Am. Bull.,1956
3. A review of the Keweenawan geology of the Lake Superior region;Halls,1966
4. Geologic evidence for crustal structure in the western Lake Superior basin;White,1966
5. North Shore volcanic group;Green,1973