韓国観光公社
In March 2011, Girl's Day digitally released "Girl's Day Party #3", with the single "Twinkle Twinkle" ("반짝반짝"). The song was a commercial success, ranking 4th on Melon's digital monthly chart in April. Overall, the song ranked 39th on the service's annual chart. On May 7 the group performed in their first overseas concert held in Taiwan. The concert was organized by the Korea Tourism Organization, and also featured performances by U-KISS and Super Junior M.