1. Lower Cretaceous Floras of western Canada;Bell;Geological Survey of Canada Memoir,1956
2. Flora of the Upper Cretaceous Nanaimo group of Vancouver Island, British Columbia;Bell;Geological Survive of Canada Memoir,1957
3. Stratigraphy and Structures of the Okhotsk-Chukotka Volcanogenic Belt;Beliy,1977
4. Observations sur les végétaux fossils renfermés dans les grès de Hoer en Scanie;Brongniart;Annales des Sciences Naturelles,1825