著者名,書名,版表示,出版者名,出版年,シリーズ名,番号,ISBN,ISSN,URL "Willits, Joseph H.",Steadying employment : with a section devoted to some facts on unemployment in Philadelphia : the investigation forming the basis for this study was carried on in the Department of Public Works of the city of Philadelphia,,American Academy of Political and Social Science,1916,Annals of the American Academy of Political and Social Science,,,,https://cir.nii.ac.jp/crid/1130282272710623744