Yuga-Vibhāga and Kāla-Pramāṇa
Measures of Time and the Four Yugas
अन्तरिक्षे समुद्रि च पाताले पर्वतेषु च / इज्या दानं तपः सत्यं त्रेतायां धर्म उच्यते
antarikṣe samudri ca pātāle parvateṣu ca / ijyā dānaṃ tapaḥ satyaṃ tretāyāṃ dharma ucyate
In the sky, in the ocean, in Pātāla, and upon the mountains, the dharma of the Tretā Yuga is declared to be worship by sacrifice, giving, austerity, and truth.