Gobhilagrihyasutra 4.2.39

4.2.39

kurv ity ukte, kam̐se carū samavadāya mekṣaṇeno 'paghātaṃ juhuyāt svāhā somāya pitṛmata iti pūrvāṃ, svāhā 'gnaye kavyavāhanāya ity uttarām.-

After they have replied, 'Offer it,' he should cut off (the prescribed portions) from the two messes of cooked food (Sûtra 14), (and should put those portions) into the brazen vessel. He then should sacrifice, picking out (portions of the Havis) with the pot-ladle, the first (oblation) with (the words), 'Svâhâ to Soma Pitrimat,' the second with (the words), 'Svâhâ to Agni Kavyavâhana' (MB. II, 3, 1. 2).