United States. Bureau of Labor Statistics. "Occupational Wage Survey: Allentown-Bethlehem-Easton, Pennsylvania-New Jersey, February 1963 : Bulletin of the United States Bureau of Labor Statistics, No. 1345-45,"
Occupational Wage Survey
(1963).
https://fraser.stlouisfed.org/title/4510/item/497739, accessed on June 14, 2025.