https://www.usgs.gov/publications/conceptual-and-numerical-models-groundwater-flow-ogallala-and-arikaree-aquifers-pine
Conceptual and numerical models of groundwater flow in the Ogallala and Arikaree aquifers, Pine...
The Ogallala and Arikaree aquifers are the largest sources of groundwater on the Pine Ridge Indian Reservation and are used extensively for irrigation and...
https://digitalcommons.unl.edu/museumbulletin/23/
"The Pipy Concretions of the Arikaree" by C. Bertrand Schultz
The pipy concretions of the Arikaree (lower Miocene) of Nebraska and adjacent states were first described by Nelson Horatio Darton (1899, p. 743) as...
pipyconcretionsbertrandschultz