Cita APA (7th ed.)

Helmus, N. (2001). Frei Otto (1925). DAM Architektur Jahrbuch.

Cita Chicago (17th ed.)

Helmus, Norbert. "Frei Otto (1925)." DAM Architektur Jahrbuch 2001.

Cita MLA (8th ed.)

Helmus, Norbert. "Frei Otto (1925)." DAM Architektur Jahrbuch, 2001.