1. Trepostome and cystoporate bryozoans from the Lexington limestone and the Clays Ferry formation (Middle and Upper Ordovician) of Kentucky Author/Creator: Karklins, Olgerts L., 1924- Publication/Creation: Alexandria, Va. : For sale by the Distribution Branch, U.S. Geological Survey Resource Type: Book Is Part Of: U.S. Geological Survey professional paper, no. 1066 A-N. Access & Availability: Loading