Kenji Nakagawa, Yosuke Hashimoto, Hokuto Sunami, Mami Saito, Katsuichiro Nunoo, Ai Nomura. The Kanji Learning Website for EPA Care Worker Trainees, "Kaigo-no-Kanji Supporter" (Learning Support for Kanji Vocabulary in Caregiving Field). 2018. 5. 1. 1-12