四分律刪補隨機羯磨 2.119

2.119

"The saṃgha has already approved 'appointing Bhikṣuṇī N.N., for the sake of the saṃgha of bhikṣuṇīs, to go every half-month to the saṃgha of bhikṣus to seek instruction.' Because the saṃgha approves and is silent, thus is this matter maintained."