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 United States. Bureau of War Risk Insurance,Annual report of the Director of the Bureau of War Risk Insurance : for the fiscal year ended June 30,,Government Printing Office,1920,Document,,,,https://cir.nii.ac.jp/crid/1130282271305595136