《史记·三十世家·三王世家》
康叔年幼，周公在三公之位，而伯禽在鲁封国，那是因为封爵位时，还没成年。
康叔之年幼，周公在三公之位，而伯禽据国於鲁，盖爵命之时，未至成人。
Duke Kang was young, and Duke of Zhou was in the position of the Three Excellencies, while Boqin was enfeoffed in Lu, because when the title was enfeoffed, he was not yet an adult.