United States. Patent Office. (1931). Plant pat. [United States Patent Office].
Chicago Style (17th ed.) CitationUnited States. Patent Office. Plant Pat. [Washington, D.C.]: [United States Patent Office], 1931.
MLA (9th ed.) CitationUnited States. Patent Office. Plant Pat. [United States Patent Office], 1931.
Warning: These citations may not always be 100% accurate.