Western and arctic Canadian biostratigraphy : the proceedings of the P. S. Warren Biostratigraphy Symposium organized by the Geological Association of Canada and the Edmonton Geological Society, held at the University of Alberta, Edmonton, Alberta, May 19, 1976 - Stelck, C. R., 1917-; Chatterton, B. D. E. (Brian D. E.) (Geological Association of Canada special paper, 1978)