《宋书·志·卷十八》
有种说法认为汉代用紫生夹囊装上奏表章，以便携带，不知是否确实。
或云汉代以盛奏事，负荷以行，未详也。
There is a saying that the purple clip bag was used to hold the memorial in the Han Dynasty, for easy carrying, but it is not sure whether it is true.