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
"Lehtonen, Tapani",A note on the comparison of two sums of exponentially distributed random variables,,[Helsinki School of Economics],1987,Helsingin Kauppakorkeakoulun julkaisuja,,9517003390,,https://cir.nii.ac.jp/crid/1130282270473019136