Nathaniel J. Schaepe, Anthony M. Coleman, Ronald B. Zelt: Documentation of particle-size analyzer time series, and discrete suspended-sediment and bed-sediment sample data collection, Niobrara River near Spencer, Nebraska, October 2014 (= USGS [Hrsg.]: U.S. Geological Survey Data Series. Nr.1079). 2018, S.1, doi:10.3133/ds1079.
Michael P. Gutzmer, Justin W. King, David P. Overhue: Environmental Impacts in the Vicinity of Spencer Hydropower Dam During Sluicing Activities in the Niobrara River, Nebraska. In: Nebraska Academy of Sciences (Hrsg.): Transactions of the Nebraska Academy of Sciences and Affiliated Societies. Nr.81, 1996, S.1 (englisch, Online abrufbar auf unl.edu).