United States. Bureau of Labor Statistics. "Occupational Wage Survey: Muskegon-Muskegon Heights, Michigan, May 1961 : Bulletin of the United States Bureau of Labor Statistics, No. 1285-69,"
Occupational Wage Survey
(July 1961).
https://fraser.stlouisfed.org/title/4510/item/495919, accessed on June 11, 2025.