《贞观政要·卷五·论忠义》
突通三个儿子来应选，只有一匹不好的马，张道源的儿子穷得无法维持生计，没有见陛下有一句话涉及这件事。
通子三人来选，有一匹羸马，道源儿子不能存立，未见一言及之。
Tutong’s three sons came to participate in the selection. There was only one bad horse. Zhang Daoyuan’s son was so poor that he could not make a living. He did not hear Your Majesty say a word about this matter.