Śatapatha Brāhmaṇa ("of a hundred paths") 13.4.3.8

13.4.3.8

atha caturthe'han evamevaitāsviṣṭiṣu saṃsthitāsveṣaivāvṛdadhvaryaviti havai hotarityevādhvaryuḥ somo vaiṣṇavo rājetyāha tasyāpsaraso viśastā imā āsata iti yuvatayaḥ śobhanāḥ upasametā bhavanti tā upadiśatyaṅgiraso vedaḥ so yamityaṅgirasāmekam parva vyācakṣāṇa ivānudra>

And on the fourth day, after those (three) offerings have been performed in the same way, there is the same course of procedure. 'Adhvaryu!' he (the Hotri) says.--'Havai hotar!' replies the Adhvaryu.--'King Soma Vaishnava,' he says; 'his people are the Apsaras, and they are staying here;'--handsome maidens have come thither: it is these he instructs;--'The Aṅgiras are the Veda: this it is;' thus saying, let him go over one section of the Aṅgiras, as if reciting it. The Adhvaryu calls in the same way (on the masters of lute-players), but does not perform the Prakrama oblations.