Posuto fukushi kokka no fukushi kyoukyuu taisei : fukushi tagen shugi apurōchi no tenkai

Nishio minoru kokugo kyouikuron no tankyuu : gengo katsudou shugi gengo seikatsu shugi no tenkai to hatten

Kankoku ni okeru roujin no zaitaku fukushi ni kansuru kenkyuu : omoni nihon to hikakushite kankoku no roujin no zaitaku fukushi seisaku o tenbousuru