Yatkola, D. A., 1978. Tertiary Stratigraphy of the Niobrara River Valley, Marsland Quadrangle, Western Nebraska (GSP-19): 27 pp., size 8.5" x 11". Description: In 1973, the author's dissertation proposal involved mapping the lithologic units exposed in the Niobrara River valley between Agate and Marsland and a study of the vertebrate fossils, including their biostratigraphy. His dissertation was nearing completion when the author was killed in an automobile accident near Lawrence, Kansas, on March 12, 1976. He left a typescript of the nearly complete geologic portion of his dissertation. Out of print, unbound copy available.