@article{oai:tsukuba.repo.nii.ac.jp:00017898, author = {Arikawa, Mitsuhiro and Tanaya, Shou and Maruyama, Isao and 初貝, 安弘 and HATSUGAI, Yasuhiro}, issue = {20}, journal = {Physical review B}, month = {May}, title = {Edge states of a spin-(1/2) two-leg ladder with four-spin ring exchange}, volume = {79}, year = {2009}, yomi = {ハツガイ, ヤスヒロ} }