Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Sakaguchi Kaname,Entwicklungen der relativen Deckungsbeitragsrechnung ,廣島大學經濟論叢,0386-2704,広島大学経済学会,1989-03-25,12,4,67-92,https://cir.nii.ac.jp/crid/1390572174808721792,https://doi.org/10.15027/26873