[1] kita51_p018.pdf, 3/13/2019, 7:03:46 AM, 3/27/2024, 1:14:39 PM https://www.archives.go.jp/publication/kita/pdf/kita51_p018.pdf
[2] KDDI旧蔵文書, 独立行政法人国立公文書館 | NATIONAL ARCHIVES OF JAPAN, 3/27/2024, 1:15:08 PM https://www.digital.archives.go.jp/fonds/4322147.html
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