Gobhilagrihyasutra 1.3.9

1.3.9

agnaye svāhe 'ti pūrvāṃ, tūṣṇīm uttarāṃ madhye cā 'parājitāyāṃ ca diśī 'ti sāyam;

In the evening the first (oblation) with (the formula), 'To Agni Svâhâ!' the second silently, in the middle and in the north-eastern part (of the fire);