http://pec.lib.wvu.edu/record/P20141931Pennsylvanian cycles in West Virginia. Journal article excerpt from: Illinois State Geological Survey. <em>Bulletin</em>, 60 (1931). Reger, David B. (David Bright), 1882-1958.Geology, Stratigraphic--Pennsylvania.Sedimentation and deposition.Geology--West Virginia.14256