《资治通鉴·唐纪·唐纪十三》
马周处事敏捷，性情正直，品评人物，直抒胸臆，朕近来委任他做事，多能称心如意。
马周见事敏速，性甚贞正，论量人物，直道而言，朕比任使，多能称意。
Ma Zhou's handling of matters was quick-witted, his temperament was honest and upright, he commented on people while speaking his mind directly, I have recently entrusted him to do things, which for the most part were to my liking.