《周礼·冬官考工记·磬氏&车人》
五种兵器和旌旗都在车上插好，车行时不给人以反复不定的感觉，这样的庐人就可以称做国工。
六建既备，车不反覆，谓之国工。
When the five weapons and the flags are all set up on the carriage, the carriage does not give the impression of wavering when it moves, and such a Lu person can be called a national craftsman.