"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.
thr.mlit.go.jp
"国道106号 宮古盛岡横断道路 改築事業" [National Route 106 Miyako–Morioka Connector Reconstruction Project] (in Japanese). Iwate River and National Highway Office. Retrieved 9 June 2020.
pref.iwate.jp
"岩手県の道路の略年表" [Chronology of Iwate Prefecture's roads] (PDF). Iwate Prefecture Government. Archived from the original(PDF) on 4 March 2016. Retrieved 12 June 2020.
web.archive.org
"岩手県の道路の略年表" [Chronology of Iwate Prefecture's roads] (PDF). Iwate Prefecture Government. Archived from the original(PDF) on 4 March 2016. Retrieved 12 June 2020.