@techreport{oai:kwansei.repo.nii.ac.jp:00019446,
 author = {Kitamura, Ryoma and 新海, 哲哉 and Kitamura, Ryoma and Shinkai, Tetsuya},
 issue = {120},
 month = {Aug},
 title = {Strategic Choice on Product Line in Vertically Differentiated Duopoly},
 year = {2014}
}