Abbott, W.H. (1982). Diatom biostratigraphy of the Chesapeake Group, Virginia and Maryland. Miocene of the Southeastern United States. Special Publication No. 25. Proceedings of a Symposium held December 4-5, 1980, Tallahasee, Florida, Florida Department of Natural Resources, Division of Resource Management, Bureau of Geology, 25: 23-34, 7 figs, 1 tbl.