四分比丘戒本疏 2.115

2.115

三四反抄衣戒，《祇》二十一云「風雨時得抄一邊。若袒右肩得抄左邊，若通肩帔得抄右邊，不得令肘現。」

Rules three and four, on tucking up the robe in reverse: the Mahāsāṃghika-vinaya, fascicle twenty-one, says: "During wind and rain, one may tuck up one side. If the right shoulder is bared, one may tuck up the left side; if both shoulders are covered, one may tuck up the right side; one must not let the elbow show."