1. Ash Hollow Cave A study of stratigraphic sequence in the central Great Plains;Champe;University of Nebraska Studies, new series,1946
2. Preliminary report on the geology and water resources of Nebraska west of the one hundred and third meridian;Darton;U.S. Geological Survey Professional Paper 17,1903
3. Geologic history of Ash Hollow Park, Nebraska Conservation and Survey Division;Diffendal;University of Nebraska-Lincoln, Educational Circular 5,1982
4. Report of explorations across the Great Basin of the territory of Utah for a direct wagon-route from Camp Floyd to Genoa, in Carson Valley, in 1859;Engelmann,1876
5. The Nebraska State Geological Survey and the Valentine problem;Lugn;American Journal of Science, 5th Series,1938