Śatapatha Brāhmaṇa ("of a hundred paths") 4.4.4.6

4.4.4.6

atha yānyuttamāni trīṇi juhoti | yajñaṃ vā etadajījanata yadenamatana taṃ janayitvā yatrāsya pratiṣṭhā tatpratiṣṭhāpayati tasmātsamiṣṭayajūṃṣi juhoti

And as to the three last which he offers,--in performing the sacrifice he has produced it, and, having produced it, he firmly establishes it where there is a safe resting-place for it: this is why he performs the Samishtayagus.