United States. Bureau of Labor Statistics. "December 1967," The Employment Situation (January 10, 1968). https://fraser.stlouisfed.org/title/144/item/496931, accessed on September 24, 2023.
Public Domain
United States. Bureau of Labor Statistics. "December 1967," The Employment Situation (January 10, 1968). https://fraser.stlouisfed.org/title/144/item/496931, accessed on September 24, 2023.
Public Domain