論文（英文）
Igarashi A, Ishibashi T, Shinozaki T, Yamamoto-Mitani N. Combinations of long-term care insurance services and associated factors in Japan: a classification tree model
Igarashi A, Ishibashi T, Shinozaki T, Yamamoto-Mitani N. Combinations of long-term care insurance services and associated factors in Japan: a classification tree model. BMC Health Serv Res. 2014;14:382.