APA (7th ed.) Citation

(1926). Portable methane detectors: Requirements for permissibility, tests made and fees charged. [publisher not identified].

Chicago Style (17th ed.) Citation

Portable Methane Detectors: Requirements for Permissibility, Tests Made and Fees Charged. [Washington?]: [publisher not identified], 1926.

MLA (9th ed.) Citation

Portable Methane Detectors: Requirements for Permissibility, Tests Made and Fees Charged. [publisher not identified], 1926.

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