More records regarding ChangPoGo are found in China and Japan than in Korea. Changs stories were described in Jeongnyeonjeon of Beoncheonmunjip (written by the renowned poet Dumok (803-852)) and Sindangseo (Chin Xin Tangshu; New History of Tang). In Japan, ChangPoGo was described in the Ilbonhugi (Later Chronicle of Japan), Shoku Nihongi and Ipdanggubeopsullyehaenggi (written by Ennin (794-864). All these records praised his great personality and achievements. In Korea, records regarding him have been found in Samguksagi, Samgukyusa and other places. He is the only person in Korean history to be mentioned in the official histories of three nations.
Beoncheonmunjip
This collection was written by Dumok (803-852) during the Tang Dynasty. The story of ChangPoGo was written in Vol. 6 Jeongnyeonjeon, which is the first record of ChangPoGo and Jeongnyeon.
Ipdanggubeopsullyehaenggi
This 4-volume travel journal was written by the Japanese monk Ennin (838-847) after his travels to the Buddhist ruins of the Tang Dynasty. Volumes 2 and 4 cover the story of Korea. In Volume 2, Jeoksan Beophwawon, established by General ChangPoGo, is mentioned. This collection, which covers the political situation of Northeast Asia in the early 9th century, is a valuable record in Buddhist history.
Samguksagi
This history of the Three Kingdoms was written during the Goryeo Dynasty (1145, the 23rd year of King Injongs reign) by Buk-Sik Kim. The story of ChangPoGo and Jeongnyeon are described in Volumes 10 and 11 of the Silla Bongi (the Records of Silla) and Volume 44 of Samguksagi (Yeoljeon, Vol.4).