United States. Department of the Interior. (1917). Opportunities for history teachers: Lessons of Great War in classroom; by National Board for Historical Service. GPO.
Chicago Style (17th ed.) CitationUnited States. Department of the Interior. Opportunities for History Teachers: Lessons of Great War in Classroom; by National Board for Historical Service. [Washington]: GPO, 1917.
MLA (9th ed.) CitationUnited States. Department of the Interior. Opportunities for History Teachers: Lessons of Great War in Classroom; by National Board for Historical Service. GPO, 1917.
Warning: These citations may not always be 100% accurate.