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
"Hoffmann-Jørgensen, J. (Jørgen)",Coverings of metric spaces with randomly placed balls,,"Aarhus universitet, Matematisk institut",1972,Preprint series,,,,https://cir.nii.ac.jp/crid/1130282273100130304