《旧唐书·列传·卷六十一》
琯好宾客，喜欢谈论，用兵不是他的长处，而天子利用他的不切实际的名声，希望取得实效。
琯好宾客，喜谈论，用兵素非所长，而天子采其虚声，冀成实效。
Guan likes to entertain guests and talk a lot. Using troops is not his strength, but the emperor used his unrealistic reputation to gain results.