1. North American cyclocrinitid algae;Nitecki;Fieldiana: Geol.,1970
2. Periodicity in invertebrate evolution;Newell;J. Paleontol.,1952
3. Repetitive benthonic communities in the Maquoketa Formation (Ordovician) of Minnesota;Bayer;J. Paleontol.,1967
4. Evolution of Chazyan (Ordovician) reefs of eastern U.S. and Canada;Pitcher;Can. Petrol. Geol. Bull.,1964