1. COLLINSON, C., BECKER, L. E., CARLSON, M. P., DORHEIM, F. H., JAMES, G. W., KOENIG, J. W. and SWANN, D. H. Devonian of the North‐Central Region, United States. International Symposium on the Devonian System, Calgary, 1967. Edited by: Oswald, D. H. vol. 1, pp.933–971. Calgary: Alberta Society Petroleum Geologists.
2. Plant Spores in Coal from the Horton Group (Mississippian) of Nova Scotia