https://www.nna.jp/news/result/57458#日本語パートナーズ
https://style.nikkei.com/article/DGXMZO18026980T20C17A6TY5000?channel=DF130120166018
https://www.gov-online.go.jp/sp/jpr/actualResults/pdf/201603.pdf
https://www.gov-online.go.jp/sp/jpr/voice/fy2016.html
https://www.gov-online.go.jp/sp/jpr/actualResults/pdf/201801.pdf
https://www.tokyo-cci.or.jp/shachonet/category/minato-ku.html