《宋书·志·卷十七》
考《礼记。王制》载， 居丧三年不祭祀宗庙，衹祭祀天地社稷，称为越绋行事 。
案《礼记王制》， 三年不祭，唯祭天地社稷，为越绋而行事。 
According to the Book of Rites, Rites of the Kings, one may not sacrifice to one’s family temple for three years of mourning; one may only sacrifice to Heaven, Earth, and the God of the Soil, which is known as observing mourning but still performing necessary actions.