釋氏要覽 3.267

3.267

或有同法同食。或同法別食主事三員謂之三綱。若罟綱之巨繩提之則正也。一上座（梵云悉替摩）二寺主（梵云毘呵囉莎弭）三綱維（梵云。羯磨陀那。此云知事）。

There are those with the same Dharma and the same meals, or those with the same Dharma and separate meals. The three chief monastic officers are called the three guiding ropes (sangang); like the great rope of a fishing net, when it is pulled up, the rest falls into order. First is the elder (sthavira); second is the director of the monastery (vihārasvāmin); third is the rector (karmadāna, translated here as the officer of duties).