United States. Weather Bureau. (1911). Frost data of U.S.; and length of crop-growing season as determined from average of latest and earliest dates of killing frost. [publisher not identified].
Chicago Style (17th ed.) CitationUnited States. Weather Bureau. Frost Data of U.S.; and Length of Crop-growing Season as Determined from Average of Latest and Earliest Dates of Killing Frost. [Washington]: [publisher not identified], 1911.
MLA (9th ed.) CitationUnited States. Weather Bureau. Frost Data of U.S.; and Length of Crop-growing Season as Determined from Average of Latest and Earliest Dates of Killing Frost. [publisher not identified], 1911.
Warning: These citations may not always be 100% accurate.