APA (7th ed.) Citation

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

Chicago Style (17th ed.) Citation

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

MLA (8th ed.) Citation

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

Warning: These citations may not always be 100% accurate.