APA (7th ed.) Citation

Schmidt, L. (1930). Diaphragm or ""breather'' roof for oil-storage tanks. [publisher not identified].

Chicago Style (17th ed.) Citation

Schmidt, Ludwig. Diaphragm or ""breather'' Roof for Oil-storage Tanks. Washington, D.C.: [publisher not identified], 1930.

MLA (9th ed.) Citation

Schmidt, Ludwig. Diaphragm or ""breather'' Roof for Oil-storage Tanks. [publisher not identified], 1930.