United States. Bureau of Plant Industry. (1921). Inventory of seeds and plants imported by Office of Foreign Seed and Plant Introduction during period from Apr. 1 to June 30, 1921. GPO.
Chicago Style (17th ed.) CitationUnited States. Bureau of Plant Industry. Inventory of Seeds and Plants Imported by Office of Foreign Seed and Plant Introduction During Period from Apr. 1 to June 30, 1921. [Washington]: GPO, 1921.
MLA (9th ed.) CitationUnited States. Bureau of Plant Industry. Inventory of Seeds and Plants Imported by Office of Foreign Seed and Plant Introduction During Period from Apr. 1 to June 30, 1921. GPO, 1921.
Warning: These citations may not always be 100% accurate.