アイヌ語地名リスト、P11-20 [Ainu Place Name List, pages 11-20] (PDF) (in Japanese). Office of Ainu Measures Promotion. 4 April 2018. p. 16. Archived(PDF) from the original on 10 February 2021. Retrieved 26 March 2021.
ramsar.org
rsis.ramsar.org
"Utonai-ko". Ramsar Sites Information Service. Archived from the original on 16 February 2020. Retrieved 25 March 2021.
"Utonai-ko". Ramsar Sites Information Service. Archived from the original on 16 February 2020. Retrieved 25 March 2021.
アイヌ語地名リスト、P11-20 [Ainu Place Name List, pages 11-20] (PDF) (in Japanese). Office of Ainu Measures Promotion. 4 April 2018. p. 16. Archived(PDF) from the original on 10 February 2021. Retrieved 26 March 2021.