International Union of Geological Sciences International Subcommission on Stratigraphic Classification, Geological Society of America, & Salvador, A. (1994). International stratigraphic guide: A guide to stratigraphic classification, terminology, and procedure (2nd ed.). International Union of Geological Sciences, Geological Society of America.
Παραπομπή σε μορφή Chicago (17η εκδ.)International Union of Geological Sciences International Subcommission on Stratigraphic Classification, Geological Society of America, και Amos Salvador. International Stratigraphic Guide: A Guide to Stratigraphic Classification, Terminology, and Procedure. 2nd ed. Trondheim, Norway : Boulder, Colo.: International Union of Geological Sciences, Geological Society of America, 1994.
Παραπομπή σε μορφή MLA (9th εκδ.)International Union of Geological Sciences International Subcommission on Stratigraphic Classification, et al. International Stratigraphic Guide: A Guide to Stratigraphic Classification, Terminology, and Procedure. 2nd ed. International Union of Geological Sciences, Geological Society of America, 1994.