周书
Zhoushu (or Zhou shu) – combining "Zhou" 周 "Zhou dynasty" and "shu" 書 "writing; document; book; letter" – is the earliest record of the present title. Depending upon the semantic interpretation of "shu", "Zhoushu" can be translated "Book(s) of Zhou" (cf. "Hanshu" 漢書 "Book of Han") or "Documents of Zhou" (cf. "Shujing" 書經 "Book of Documents"). In Modern Standard Chinese usage, "Zhoushu" is the title of the "Book of Zhou" history about the later Northern Zhou dynasty (557-581).