Hiranyakeshigrihyasutra 1.1.3

This is the rite for all Darvi-sacrifices.

At the end of the Mantras constantly the word Svâhâ (is pronounced).

(Oblations) for which no Mantras are prescribed (are made merely with the words), 'To such and such (a deity) svâhâ!'—according to the deity (to whom the oblation is made).

He sacrifices with the Vyâhritis, 'Bhûh! Bhuvah! Suvah!'—with the single (three Vyâhritis) and with (the three) together.

(The Mantras for the two chief oblations are), the (verse), 'Life-giving, Agni!' (Taitt. Brâhmana I, 2, 1, 11), (and),
'Life-giving, O god, choosing long life, thou whose face is full of ghee, whose back is full of ghee, Agni, drinking ghee, the noble ambrosia that comes from the cow, lead this (boy) to old age, as a father (leads) his son. Svâhâ!'

(Then follow oblations with the verses),
'This, O Varuna' (Taitt. Samh. II, 1, 11, 6),
'For this I entreat thee' (Taitt. Samh., loc. cit.), 'Thou, Agni' (Taitt. Samh. II, 5, 12, 3),
'Thus thou, Agni' (Taitt. Samh., loc. cit.),
'Thou, Agni, art quick. Being quick, appointed (by us) in our mind (as our messenger), thou who art quick, earnest the offering (to the gods). O quick one, bestow medicine on us! Svâhâ!'—(and finally) the (verse),
'Pragâpati!' (Taitt. Samh. I, 8, 14, 2).

(With the verse), 'What I have done too much in this sacrifice, or what I have done here deficiently, all that may Agni Svishtakrit, he who knows it, make well sacrificed and well offered for me. To Agni Svishtakrit, the offerer of well-offered (sacrifices), the offerer of everything, to him who makes us succeed in our offerings and in our wishes, svâhâ!'—he offers (the Svishtakrit oblation) over the easterly part of the northerly part (of the fire), separated from the other oblations.

Here some add as subordinate oblations, before the Svishtakrit, the Gaya, Abhyâtâna, and Râshtrabhrit (oblations).

The Gaya (oblations) he sacrifices with (the thirteen Mantras), 'Thought, svâhâ! Thinking, svâhâ!'—or, 'To thought svâhâ! To thinking svâhâ!' (&c.);

The Abhyâtâna (oblations) with (the eighteen Mantras), 'Agni is the lord of beings; may he protect me' (&c.).

(The words), 'In this power of holiness, in this worldly power (&c.)' are added to (each section of) the Abhyâtâna formulas.

With (the last of the Abhyâtâna formulas) 'Fathers! Grandfathers!' he sacrifices or performs worship, wearing the sacrificial cord over his right shoulder.

The Râshtrabhrit (oblations he sacrifices) with (the twelve Mantras), 'The champion of truth, he whose law is truth.' After having quickly repeated (each) section, he sacrifices the first oblation with (the words), 'To him svâhâ!' the second (oblation) with (the words), 'To them svâhâ!'

Having placed a stone near the northerly junction of the pegs (which are laid round the fire), (the teacher)—