1. Summary of ground-water hydrology of the Cambrian-Ordovician aquifer system in the northern Midwest, United States Author/Creator: Young, H. L. Publication/Creation: Denver, CO : For sale by Book and Open-File Report Sales, U.S. Geological Survey Resource Type: Book Access & Availability: Loading
2. Hydrogeology of the Cambrian-Ordovician aquifer system in the northern Midwest, United States Author/Creator: Young, H. L. Publication/Creation: Denver, CO : For sale by Books and Open-File Reports, U.S. Geological Survey Resource Type: Book Access & Availability: Loading
3. Summary of ground-water hydrology of the Cambrian-Ordovician aquifer system in the northern Midwest, United States Author/Creator: Young, H. L., author Publication/Creation: Washington : U.S. Department of the Interior, U.S. Geological Survey, 1992 Resource Type: Book Access & Availability: Loading
4. Hydrogeology of the Cambrian-Ordovician aquifer system in the northern Midwest, United States Author/Creator: Young, H. L., author Publication/Creation: Washington : U.S. Department of the Interior, U.S. Geological Survey, 1992 Resource Type: Book Access & Availability: Loading
5. Salterella from the Lower Cambrian of central Nevada, Author/Creator: Yochelson, Ellis L. 1928-2006. (Ellis Leon) Publication/Creation: Washington : U.S. Govt. Print. Off, 1970 Resource Type: Book Is Part Of: U.S. Geological Survey professional paper, no. 642-644. Access & Availability: Loading
6. Paleobiology of Climactichnites : an enigmatic Late Cambrian fossil Author/Creator: Yochelson, Ellis L. 1928-2006. (Ellis Leon) Publication/Creation: Washington, D.C. : Smithsonian Institution Press, 1993 Resource Type: Book Access & Availability: Loading
7. The Early Cambrian fossil Salterella conulata Clark in eastern North America, Author/Creator: Yochelson, Ellis L. 1928-2006. (Ellis Leon) Publication/Creation: Washington : U.S. Govt. Print. Off, 1970 Resource Type: Book Is Part Of: U.S. Geological Survey professional paper, no. 681-683. Access & Availability: Loading
8. Salterella from the Lower Cambrian of central Nevada Author/Creator: Yochelson, Ellis L. 1928-2006, (Ellis Leon), author Publication/Creation: Washington : United States Department of the Interior, Geological Survey, 1970 Resource Type: Book Access & Availability: Loading
9. The Early Cambrian fossil Salterella conulata Clark in eastern North America Author/Creator: Yochelson, Ellis L. 1928-2006, (Ellis Leon), author Publication/Creation: Washington : United States Department of the Interior, Geological Survey, 1970 Resource Type: Book Access & Availability: Loading
10. The Burgess Shale Author/Creator: Whittington, H. B. (Harry Blackmore) Publication/Creation: New Haven : Published in association with the Geological Survey of Canada by Yale University Press, [1985] Resource Type: Book Access & Availability: Loading