Folberth, O. (1957). Integration: Bulletin International. Hofmann.
Cita Chicago (17th ed.)Folberth, O. Integration: Bulletin International. Augsburg: Hofmann, 1957.
Cita MLA (8th ed.)Folberth, O. Integration: Bulletin International. Hofmann, 1957.
Atenció: Aquestes cites poden no estar 100% correctes.