 Instead, "Dongguk yeojiji" says "...one theory has it that Usan-do and Ulleung-do are the same island..." as described in "Donggug Yeoji Seunglam" (1481).Usando is displayed on the cartographs made by Chong Sang-gi (1678~1752); (1822), and (by Kim Tae-gon, 1821–1846).Japanese believe it to be Jukdo, noting the distance, shape, size, and direction., while Koreans believe it to be Liancourt and they said that Usando was a former name of Liancourt.