APA (7th ed.) Citation

United States. Patent Office & United States. Patent Office. (1921). Index of patents issued from the United States Patent Office. The Office.

Chicago Style (17th ed.) Citation

United States. Patent Office and United States. Patent Office. Index of Patents Issued from the United States Patent Office. Washington: The Office, 1921.

MLA (9th ed.) Citation

United States. Patent Office and United States. Patent Office. Index of Patents Issued from the United States Patent Office. The Office, 1921.