Oju yà Ânmun changjà Ân san'go () is a general encyclopedia written by Yi Kyugyà Âng during the late Joseon-era. It spans 60 books, covering 1,417 topics from astronomy to religion.
The document was lost until the 1920s, until member Kwà Ân Posang () found it being used as a wrapping paper for baked chestnuts. He took it to the , an organization founded in 1910 by Ch'oe Namsà Ân to publish classical Korean literature, which confirmed its authenticity.