Illuminating Engineering Society
, American Standards Association
and United States. Bureau of Labor Statistics.
Code of Lighting: Factories, Mills and Other Work Places : Bulletin of the United States Bureau of Labor Statistics, No. 556 ,
Washington:
U.S. Govt. Print. Off.,
October 1931, https://fraser.stlouisfed.org/title/4095,
accessed on August 6, 2024.