Books/Articles

American Commission on Stratigraphic Nomenclature, 1961, Code of Stratigraphic Nomenclature: American Association of Petroleum Geologists Bulletin, v. 45, no. 5, p. 645-665.

American Commission on Stratigraphic Nomenclature, 1970, Code of Stratigraphic Nomenclature (2d ed.): American Association of Petroleum Geologists, Tulsa, Okla., 45 p.

Harland, W. B., 1978, Geochronologic scales, in G. V. Cohee et al, eds., Contributions to the Geologic Time Scale: American Association of Petroleum Geologists, Studies in Geology, no. 6, p. 9-32.

North American Commission on Stratigraphic Nomenclature, 1981. Draft North American Stratigraphic Code: Canadian Society of Petroleum Geologists, Calgary, 63 p.

Online sources

Petroleum Industry Data Dictionary, American Petroleum Institute (Product Number: 038650, Document 3865), http://w3.posc.org/pidd/

Schlumberger Oilfield Glossary, http://www.glossary.oilfield.slb.com/Default.cfm