Jaiminīya (Talavakāra) Brāhmaṇa 36.209

The gods indeed desired: "May we ascend straight (añjasā) to the heavenly world."
They saw this sāman.
With it they praised.
Thereupon they indeed ascended straight to the heavenly world.
That is the straightness of the Āñjasa.
That is a heaven-procuring sāman.
Straight indeed he ascends to the heavenly world with it, who knows thus.
Now they also call it the Vairūpa.
Cattle indeed are manifold (virūpāḥ);
cattle are the Vairūpa;
thus he joins cattle to cattle.
Virūpa Āṅgirasa, desiring cattle, practiced austerity.
He saw this sāman.
With it he praised.
Thereupon he indeed obtained cattle.
That is a cattle-procuring sāman.
He obtains cattle and becomes rich in cattle, who knows thus.
And because Virūpa Āṅgirasa saw it, therefore it is called Vairūpa.

Now the Sāman of the Yokes (Dhurāṃ Sāman) running with iḷā, connected with the Rathantara.
Therefore it is performed on a Rathantara day.
The meters indeed are the yokes.
Exhausted as it were are these, namely the Chandomas.
When the Sāman of the Yokes is performed here, thereby the Chandomas are made bearing the yoke, possessed of meters, and unexhausted.
Moreover, the breaths are the yokes;
cattle are the yokes;
thus he firmly stands in breaths and in cattle.
Then the Aiḷata with three refrains, for the proper arrangement of the pressings.
Successful indeed is that which is Gāyatra and has three refrains.
Iḷa Kāvya, desiring heaven, practiced austerity.
He saw this sāman.
With it he praised.
He ascended to this world with the first refrain, to the intermediate space with the second, to that [sky] with the third.
He ascended to these three worlds.
Then indeed he was established in the heavenly world.
That is a heaven-procuring and establishing sāman.
He goes to the heavenly world, and is established in the heavenly world, who knows thus.
And because Iḷa Kāvya saw it, therefore it is called Aiḷata.
Now the Saumitra, slaying the rival, possessed of Indra.
He slays his hating rival, and Indra comes to his call, who knows thus.