Natyashastra
चक्रुस्ते नाम पिण्डीनां बन्धमासां सलक्षणम् । ईश्वरस्येश्वरी पिण्डी नन्दिनश्चापि पट्टसी ॥ २५३॥
The Piṇḍīs are named based on their specific forms, with the Piṇḍī of Śiva being Vṛṣa, the Piṇḍī of Nandī being Paṭṭisī, and the Piṇḍī of Śakra (Indra) being Airāvatī.
english translation
cakruste nAma piNDInAM bandhamAsAM salakSaNam । IzvarasyezvarI piNDI nandinazcApi paTTasI ॥ 253॥
hk transliteration by Sanscript