《礼记·丧服小记》
如果国君出访久而未归，等到回国后才闻知上述亲属凶讯，在这种情况下，国君要迫服丧服，国君的随从之臣也要跟着追服丧服；至于其他臣子，在丧期之内就跟着服丧，过了丧期的就不再跟着追服。
哭皆于其次。
If the monarch visits for a long time and does not return, and only hears the news of the death of the above-mentioned relatives after returning to the country, the monarch will have to mourn, and the monarch’s entourage will also have to catch up with the mourning; as for other courtiers, they will follow the mourning within the mourning period. Those who have passed the mourning period will no longer catch up.