1. Al-Jazari, Ibn al-Razzaz. (1206). Kitab fi ma rifat al-hiyal al-handasiya. D. R. Hill (Ed. and Trans.). (1974). The book of knowledge of ingenious mechanical devices. Dordrecht, The Netherlands: Reidel.
2. Annals of Gwanghaegun (Ganghaegun Ilgi). (1616). 103.
3. Annals of Hyeonjong (Hyeonjong Sillok). (1669). 17, 35ab; 21, 55a.
4. Annals of Jungjong (Jungjong Sillok). (1536). 82, p. 33.
5. Annals of Sejong (Sejong Sillok). 61(1433), 65 (1434), 77(1437), 80 (1438).