Nan Zhou Yi Wu Zhi (Annals of Unusual Things from the Southern Regions) by Wan Zhen (the State of Wu during the Three Kingdoms Period)

Nanhai Zhudao was recorded in Nan Zhou Yi Wu Zhi by Wan Zhen, prefecture chief of Danyang, the State of Wu in the Three Kingdoms Period (AD 220-280). Tai Ping Yu Lan (Readings of the Taiping Era) compiled in the Taiping Xingguo Years in the Song Dynasty (AD 977-983) contains a number of texts lost in Nan Zhou Yi Wu Zhi. One of them says "Going northeastward from the southeast of the estuary at Dunxun, eight hundred li from Gouzhi, there are gigantic Qitou rising above the Zhanghai, where the water is shallow and interspersed with Cishi." In the description, Qitou, the Zhanghai and Cishi are generalized terms referring to the South China Sea, the islands and reefs of the South China Sea, shoals and submerged reefs respectively.