United States. Bureau of Labor Statistics. "Association of Governmental Officials in Industry of the United States and Canada : Fifteenth Annual Convention, New Orleans, La, May 21-24, 1928 : Bulletin of the United States Bureau of Labor Statistics, No. 480," Proceedings of the ... Annual Convention of the Association of Governmental Labor Officials of United States and Canada (1929). https://fraser.stlouisfed.org/title/3907/item/493138, accessed on March 10, 2025.