Author,Title,Edition,Publisher,Year,Series,Number,ISBN,ISSN,URL
"Conyngton, Mary K. and Speek, Peter Alexander and United States. Bureau of Labor Statistics","Public service retirement systems : United States, Canada, and Europe",,U.S. G.P.O.,1929,Bulletin,,,,https://cir.nii.ac.jp/crid/1130282269834584064