Yāska's Nirukta 7.20

7.20

``pra nūnam jātavedasam aśvam hinota vājinam/
idam no barhir āsade''.][804]
prahinuta jātavedasam karmabhiḥ samaśnuvānam/
api vā upamā arthe syād aśvam iva jātavedasam iti/
idam no barhir āsīdatv iti/
tad etad ekam eva jātavedasam gāyatram tṛcam daśatayīsu vidyate/[804]
yat tu kiṃcid āgneyam tat jātavedasānām sthāne yujyate/[804]
sa[student].na manyeta ayam eva agnir ity,.apy ete uttare jyotiṣī jātavedasī ucyete/
tato nu madhyamah/[804]
``abhi pravanta samanā iva yoṣā iti/
tat purastād vyākhyātam/[804]
atha asāv āditya.''.ud u tyam jātavedasam''.iti,.tad upariṣṭād vyākhyāsyāmah/[804]
yas tu sūktam bhajate yasmai havis nirupyate ayam eva so agnir jātavedas1/
nipātam eva ete uttare jyotiṣī etena nāmadheyena bhajete/[804]