Yōga Sūtra 2.50

बाह्याभ्यन्तरस्तम्भवृत्तिः देशकालसङ्ख्याभिः परिदृष्टो दीर्घसूक्ष्मः।

bāhyābhyantarastambhavr̥ttiḥ dēśakālasaṅkhyābhiḥ paridr̥ṣṭō dīrghasūkṣmaḥ।

[बाह्य अभ्यन्तर स्तम्भ वृत्तिः देश काल सङ्ख्याभिः परिदृष्टो दीर्घ सूक्ष्मः।
bāhya = outside; abhyantara = and inside; stambha = suspension; vr̥ttiḥ = acts; dēśa = place; kāla = time; saṅkhyābhiḥ = counts; paridr̥ṣṭō = regulated as per; dīrgha = prolonged; sūkṣmaḥ = subtle;]

The acts of suspending air outside or inside must be regulated based on place, time, and counts, making it prolonged and subtle.