1. Ordovician tidalites in the unmetamorphosed sedimentary fill of the Brent Meteorite Crater, Ontario;Beales,1975
2. Meteorite scars in ancient rocks;Boon;Field and Lab,1936
3. Conodonts from the Joachim (middle Ordovician) of Missouri;Branson;University of Missouri Studies,1934
4. Conodonts from the grassy creek shale of Missouri;Branson;University of Missouri Studies,1934