United States. Bureau of Labor Statistics. "Employed and Unemployed Persons by Occupation, Not Seasonally Adjusted," in United States. Bureau of Labor Statistics. "May 2017," The Employment Situation (June 2, 2017) : 24-24. https://fraser.stlouisfed.org/title/144/item/552376/toc/521430 , accessed on May 8, 2024.