1. American Commission on Stratigraphic Nomenclature: Report 2: Nature, usage, and nomenclature of time-stratigraphic and geologic-time units. Bull. Amer. Assoc. Petrol. Geol.,36, 1627–1638, Tulsa, Okla., 1952.
2. —: Report 4: Nature, usage, and nomenclature of rock-stratigraphic units. Ibid.,40, 2003 bis 2014, 1956.
3. —: Report 5: Nature, usage, and nomenclature of biostratigraphic units. Ibid.,41, 1877–1891, 1 Abb., 1957.
4. Arkell, W. J.: Comments on stratigraphic procedure and terminology. Amer. J. Sci.,254, 457–467, New Haven, Conn., 1956.
5. Ashley, G. H.: Stratigraphic nomenclature. Bull. geol. Soc. Amer.,43, 469–476, New York 1932.