United States. Division of Labor Standards. (1939). National standards for steamfitting apprenticeship, including suggestions for putting national standards into operation in local communities. [s.n.].
Chicago Style (17th ed.) CitationUnited States. Division of Labor Standards. National Standards for Steamfitting Apprenticeship, Including Suggestions for Putting National Standards into Operation in Local Communities. [Washington]: [s.n.], 1939.
MLA (9th ed.) CitationUnited States. Division of Labor Standards. National Standards for Steamfitting Apprenticeship, Including Suggestions for Putting National Standards into Operation in Local Communities. [s.n.], 1939.
Warning: These citations may not always be 100% accurate.