Dewhurst, J. Frederic (James Frederic), 1895- , Tupper, Ernest Allen, 1902- and Wharton School. Industrial Research Department. Social and Economic Character of Unemployment in Philadelphia, April, 1929 : Bulletin of the United States Bureau of Labor Statistics, No. 520 , Washington: U.S. Govt. Print. Off., June 1930, https://fraser.stlouisfed.org/title/4078, accessed on November 15, 2024.