Copenhagen Symposium on Functioning of Terrestrial Ecosystems at the Primary Production Level & Eckardt, F. (1968). Functioning of terrestrial ecosystems at the primary production level: Proceedings of the Copenhagen Symposium held in Copenhagen from 24 to 30 July 1965. United Nations Educational, Scientific and Cultural Organization.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Copenhagen Symposium on Functioning of Terrestrial Ecosystems at the Primary Production Level و F.E Eckardt. Functioning of Terrestrial Ecosystems at the Primary Production Level: Proceedings of the Copenhagen Symposium Held in Copenhagen from 24 to 30 July 1965. Paris: United Nations Educational, Scientific and Cultural Organization, 1968.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Copenhagen Symposium on Functioning of Terrestrial Ecosystems at the Primary Production Level و F.E Eckardt. Functioning of Terrestrial Ecosystems at the Primary Production Level: Proceedings of the Copenhagen Symposium Held in Copenhagen from 24 to 30 July 1965. United Nations Educational, Scientific and Cultural Organization, 1968.