Skinner, Morris F.; Hibbard, Claude William, 1905-1973.; Gutentag, Edwin D., 1931-; Smith, G. R.; Lundberg, John G.; Holman, J. Alan.; Feduccia, Alan.; Rich, Pat Vickers.
(New York : [American Museum of Natural History], 1972)
"A study of the early Pleistocene rocks of the non-glaciated region of north-central Nebraska shows that a paleovalley fill (Keim Formation, new name) that contained the Sand Draw local fauna was preglacial. The stratigraphic ...