石狩川 (in Japanese). Ministry of Land,Infrastructure and Transport and Tourism Hokkaido Regional Development Bureau. Archived from the original on 2009-04-01. Retrieved 2009-05-04.
web.archive.org
石狩川 (in Japanese). Ministry of Land,Infrastructure and Transport and Tourism Hokkaido Regional Development Bureau. Archived from the original on 2009-04-01. Retrieved 2009-05-04.