Mahabharata 14.24.9

प्राणापानाविदं द्वंद्वमवाक्चोर्ध्वं च गच्छतःव्यानः समानश्चैवोभौ तिर्यग्द्वंद्वत्वमुच्यते

prāṇāpānāvidaṃ dvaṃdvamavākcordhvaṃ ca gacchataḥvyānaḥ samānaścaivobhau tiryagdvaṃdvatvamucyate

Our plain-language meaning of this verse is waiting for scholar review.