Citazione Stile APA (7a Edizione)

International Geological Congress Copenhagen, Denmark, & Sorgenfrei, T. (1960). Report of the twenty-first session, Norden: Denmark, Finland, Iceland, Norway, Sweden, 1960. Berlingske bogtr..

Citazione stile Chigago Style (17a edizione)

International Geological Congress Copenhagen, Denmark, e Theodor Sorgenfrei. Report of the Twenty-first Session, Norden: Denmark, Finland, Iceland, Norway, Sweden, 1960. Copenhagen: Berlingske bogtr., 1960.

Citatione MLA (8a ed.)

International Geological Congress Copenhagen, Denmark, e Theodor Sorgenfrei. Report of the Twenty-first Session, Norden: Denmark, Finland, Iceland, Norway, Sweden, 1960. Berlingske bogtr., 1960.