平成25年 統計りゅうがさき [2013 Statistics, Ryūgasaki] (PDF) (in Japanese). Japan: Ryūgasaki City. p. 2. Retrieved 16 September 2014.
市民憲章、市章、市の花・木・鳥 [Townspeople's charter, city symbol, the city's flower, tree and bird] (PDF) (in Japanese). Japan: Ryūgasaki City. Retrieved 16 September 2014.
市長プロフィール [Mayor Profile]. Ryūgasaki City (in Japanese). January 18, 2022. Retrieved September 14, 2023.
平成25年 統計りゅうがさき [2013 Statistics, Ryugasaki] (PDF) (in Japanese). Japan: Ryūgasaki City. p. 59. Retrieved 16 September 2014.