@phdthesis{oai:tsukuba.repo.nii.ac.jp:00020897,
 author = {土井, 幸雄 and Doi, Yukio},
 month = {},
 note = {1984},
 school = {筑波大学, University of Tsukuba},
 title = {On the structure of Hopf modules},
 year = {1985}
}