"一般国道の路線別、都道府県別道路現況" [Road statistics by General National Highway route and prefecture] (PDF) (in Japanese). Ministry of Land, Infrastructure, Transport and Tourism. Retrieved 19 February 2020.
"一般国道の路線別、都道府県別道路現況"(PDF) (in Japanese). Ministry of Land, Infrastructure, Transport and Tourism. Retrieved 10 October 2019.
thr.mlit.go.jp
"ja:一般国道7号" (in Japanese). Ministry of Land, Infrastructure, Transport and Tourism, Tohoku Regional Development Bureau. Archived from the original on 1 May 2016. Retrieved 16 October 2019.
ushukaido.com
"羽州街道交流会" (in Japanese). 2017. Retrieved 12 October 2019.
web.archive.org
"ja:一般国道7号" (in Japanese). Ministry of Land, Infrastructure, Transport and Tourism, Tohoku Regional Development Bureau. Archived from the original on 1 May 2016. Retrieved 16 October 2019.
wikisource.org
ja.wikisource.org
"一般国道の路線を指定する政令" (in Japanese). Retrieved 10 October 2019 – via Wikisource.