佛祖歷代通載 12.59

12.59

（庚寅）　改天授○二月辛酉。后策貢士於洛城殿。殿試始此○九月改元建國。號曰周。至朔同日用周正。

(Gengyin [690 CE]) The era was changed to Tianshou. ○ In the second month, on the xinyou day, the Empress tested the tribute scholars in the Luocheng Hall; the palace examination began with this. ○ In the ninth month, the era was changed and the state founded, with the dynastic title Zhou. The winter solstice and the new moon coincided on the same day, and the Zhou calendar was adopted.