APA (7th ed.) Citation

United States. Forest Service. (1912). Signs, symbols and colors; supplement to Instructions for making forest surveys and maps. [publisher not identified].

Chicago Style (17th ed.) Citation

United States. Forest Service. Signs, Symbols and Colors; Supplement to Instructions for Making Forest Surveys and Maps. Washington: [publisher not identified], 1912.

MLA (9th ed.) Citation

United States. Forest Service. Signs, Symbols and Colors; Supplement to Instructions for Making Forest Surveys and Maps. [publisher not identified], 1912.