《新唐书·列传·卷二十九》
太子派张行成到太宗的行营拜望，太宗见了高兴得不得了，赏赐慰劳特别优厚。
太子使行成诣行在，帝见悦甚，赐劳尤渥。
The Crown Prince dispatches Zhang Xingcheng to pay respects at Taizong's military encampment. Taizong is overjoyed on seeing him and grants him especially generous rewards as a token of appreciation.