Yongbieocheonga (Songs of Dragons Flying in Heaven) is a musical text that eulogizes the founding of the Joseon Dynasty, and is the first text ever written in the Korean alphabet, or Hunminjeongeum (lit. The Correct Sounds for the Instruction of the People), which is nowadays more commonly known as Hangeul. It is of immense historical value as, along with Worincheongangjigok (Songs of the Moon's Reflection on a Thousand Rivers), it is highly representative of the musical texts produced during the Joseon Dynasty. It is also a valuable material for studies of the Korean language and bibliography during the reign of King Sejong of the Joseon Dynasty. Yongbieocheonga is composed of ten volumes, of which these three (volumes 8 to 10) are preserved at Keimyung University. The characters are written in the calligraphic style of SongXue (whose name derives from the pen-name of the famous Chinese calligrapher Zhao Mengfu), which was popular in the early days of the Joseon Dynasty. The block styles are consistent with the styles of the early Joseon Dynasty, consisting of black lines and inward-facing heugeomi (black-colored fish tail shapes) at the top and bottom of the pansim (center of the block), suggesting that these books may be first editions. However, as traces can be seen in places where corrections were made to the engravings, these books are presumed to have been printed after corrections were made to the woodblocks of the first edition.