United States. Bureau of Labor Statistics. "Employed and Unemployed Persons by Occupation, Not Seasonally Adjusted," in United States. Bureau of Labor Statistics. "October 2012," The Employment Situation (November 2, 2012) : 24-24. https://fraser.stlouisfed.org/title/144/item/494867/toc/506647 , accessed on April 19, 2024.