Amāvasyā-Pitṛtarpaṇa: Purūravas and the Soma-Based Ancestral Offering (अमावस्या-पितृतर्पण / सोमतर्पण-विधि)
सोम इड्वत्सरः प्रोक्तो वायुश्चैवानुवत्सरः / रुद्रस्तु वत्सरस्तेषां पञ्चाब्दास्ते युगात्मकाः
soma iḍvatsaraḥ prokto vāyuścaivānuvatsaraḥ / rudrastu vatsarasteṣāṃ pañcābdāste yugātmakāḥ
Soma is declared to be Iḍvatsara, and Vāyu to be Anuvatsara. For them, Rudra is Vatsara; these five “abda” are yuga in their very essence.