United States. Bureau of Labor Statistics. "Occupational Wage Survey: Davenport-Rock Island-Moline, Iowa-Illinois, October 1961 : Bulletin of the United States Bureau of Labor Statistics, No. 1303-17,"
Occupational Wage Survey
(1962).
https://fraser.stlouisfed.org/title/4510/item/497593, accessed on February 12, 2025.