Liancourt Rocks dispute Japan. In 1954, Japan proposed a reference to the International Court of Justice, which South Korea rejected, believing that the Liancourt Rocks are irrefutably South Korean territories, and thus should not be dealt through diplomatic negotiations or judicial settlement between South Korea and Japan. There are conflicting interpretations about the historical state of sovereignty over the islets. Korean claims are partly based on references to a Korean island called "Usan-do" in various historical records, maps and encyclopedias such as the "Samguk Sagi", "Annals of the Joseon Dynasty", "Dongguk Yeoji Seungnam" (), and "Dongguk munheon bigo" (). According to the Korean
Liancourt Rocks to the islets every day. Tour companies charge around 350,000 Korean won per person (about US$250 ). South Korea has carried out construction work on the Liancourt Rocks, by 2009 the islands had a lighthouse and helicopter pad, and a police barracks. In 2007, two desalinization plants were built capable of producing 28 tons of clean water every day. Both of the major South Korean telecommunications companies have installed cellular telephone towers on the islets. American and French whaleships cruised for right whales off the rocks between 1849 and 1892. Sovereignty over the islands has been an ongoing point of