Hours and Earnings in Anthracite and Bituminous Coal Mining: Anthracite--1919 and 1920, Bituminous--1919 : Bulletin of the United States Bureau of Labor Statistics, No. 279
United States. Bureau of Labor Statistics. "Hours and Earnings in Anthracite and Bituminous Coal Mining: Anthracite--1919 and 1920, Bituminous--1919 : Bulletin of the United States Bureau of Labor Statistics, No. 279," Wages and Hours of Labor in Bituminous-Coal Mining (April 1921). https://fraser.stlouisfed.org/title/4021/item/493033, accessed on December 4, 2023.
- Bulletin of the United States Bureau of Labor Statistics
- Wages and Hours of Labor Series
- Wages and Hours of Labor Series
- Bulletin of the United States Bureau of Labor Statistics
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