United States. Bureau of Standards. (1938). Circular of the Bureau of Standards, C421: Spectral-Ttransmissive Properties and Use of Colored Eye-Protective Glasses. [s.n.].
Chicago Style (17th ed.) CitationUnited States. Bureau of Standards. Circular of the Bureau of Standards, C421: Spectral-Ttransmissive Properties and Use of Colored Eye-Protective Glasses. [Washington]: [s.n.], 1938.
MLA (9th ed.) CitationUnited States. Bureau of Standards. Circular of the Bureau of Standards, C421: Spectral-Ttransmissive Properties and Use of Colored Eye-Protective Glasses. [s.n.], 1938.
Warning: These citations may not always be 100% accurate.