Patanjali Yoga Sutra 2.50
Sanskrit Sutra
बाह्याभ्यन्तरस्तम्भवृत्तिः देशकालसंख्याभिः परिदृष्टो दीर्घसूक्षमः॥५०॥
Swami Vivekananda's translation
Its modifications are either external or internal, or motionless, regulated by place, time, and number, either long or short.
Chapter link: Yoga Sutra Chapter 2

Muni's Play