Kolodrubetz, Walter W. (Walter William). Pension Plans Under Collective Bargaining : Normal Retirement, Early and Disability Retirement, Fall 1959 : Bulletin of the United States Bureau of Labor Statistics, No. 1284 , Washington, D.C: G.P.O., February 1961, https://fraser.stlouisfed.org/title/4559, accessed on November 15, 2024.