Author,Title,Edition,Publisher,Year,Series,Number,ISBN,ISSN,URL
United States. Bureau of Labor Statistics,"Pension plans under collective bargaining : vested rights, compulsory retirement, types and amounts of benefits",,"U. S. Dept. of Labor, Bureau of Labor Statistics,For sale by the Supt. of Docs., U.S. Govt. Print. Off.",1953,Bulletin,,,,https://cir.nii.ac.jp/crid/1130282272061000320