@phdthesis{oai:tsukuba.repo.nii.ac.jp:00021017,
 author = {横田, 巧 and Yokota, Takumi},
 month = {},
 note = {2009, Includes bibliographical references},
 school = {筑波大学, University of Tsukuba},
 title = {Comparison geometry of ancient solutions to the Ricci flow},
 year = {2009}
}