《礼记·服问》
大夫的嫡子为国君、为国君的夫人、为国君的太子所穿的丧服，和士为国君、为国君的夫人、为国君的太子所穿的丧服一样。
大夫之适子为君、夫人、大子，如士服。君之母，非夫人，则群臣无服。
The mourning clothes of the eldest son of the doctor to the monarch, the monarch's wife, and the monarch's prince are the same as those of the mourning clothes of the emperor to the monarch, the monarch's wife, and the monarch's prince.