Śatapatha Brāhmaṇa ("of a hundred paths") 6.2.2.10

6.2.2.10

ubhayīrgāyatrīśca triṣṭubhaścānvāha | tāsāmukto bandhuruktamvevānvṛcaṃ dvādaśāpriyastāsāmukto bandhuruktamvevānvṛcam prājāpatyaḥ paśupuroḍāśo 'tro sa kāma upāpta iti ha smāha māhitthiryaṃ carakāḥ prājāpatye paśāvāhuriti

He recites both gâyatrî and trishtubh verses: their significance has been told; and (what applies to) the order of the verses has been told. There are twelve Âprî-verses: their significance has been told; and (what applies to) the order of the verses has been told. The animal cake belongs to Pragâpati: 'Therein then that wish was obtained,' Mâhitthi once said,--'which the Karakâs say is in the victim to Pragâpati.'