《元史·本纪·卷十四》
二十一日，桑哥上奏说： 北安王的宰相府没有印信，唯独安西王的相国有印信，确是一个不恰当的先例，请收回安西王相府的印信。
戊寅，桑哥言： 北安王相府无印，而安西王相独有印，实非事例，乞收之。
On the 21st day, Sangge submitted a memorial saying: The prime minister's mansion of the King of Beian has no official seal, while only the prime minister of the King of Anxi has an official seal, which is indeed an inappropriate precedent. Please take back the official seal of the prime minister's mansion of the King of Anxi.