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| Pabian, Roger K. (1971) The Minerals and Gemstones of Nebraska. Educational Circular 2. University of Nebraska - Conservation and Survey Divsion |
| Woolley, A. R. (1987) Alkaline Rocks and Carbonatites of the World. Part 1: North and South America. |
| Kettler, Richard M., Blessington, Michael Joseph, Verplanck, Philip L., And Farmer, G. Lang (2014) The Elk Creek Carbonatite Complex. Geological Society of America Abstracts with Programs. Vol. 46, No. 4, p.21 |