Occupational Employment Statistics, 1960-70 : Bulletin of the United States Bureau of Labor Statistics, No. 1738
United States. Bureau of Labor Statistics. "Occupational Employment Statistics, 1960-70 : Bulletin of the United States Bureau of Labor Statistics, No. 1738," Occupational Employment Statistics (1972). https://fraser.stlouisfed.org/title/4792/item/498880, accessed on March 28, 2024.