Researching the collection and utilization of overseas Japan-related sources through multi-archival methods.Japan Society for the Promotion of Science: Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)HOYA TORU Hakoishi Hiroshi Okamoto Makoto Tani Akiyoshi Azuma Shunsuke Fumoto Shinichi Sasaki Toshikazu Vasilii Schepkin Vadim Klimov Sergey Cherniavskii Valentin Smirnov Peng Hao