Śatapatha Brāhmaṇa ("of a hundred paths") 4.3.5.22

4.3.5.22

taṃ catasṛṇāṃ dhārāṇāmāgrayaṇaṃ gṛhṇāti | ādityānāṃ vai tṛtīyasavanamādityānvā anu gāvastasmādidaṃ gavāṃ caturdhāvihitaṃ payastasmāccatasṛṇāṃ dhārāṇāmāgrayaṇaṃ gṛhṇāti

Thus he draws the Âgrayana graha from four streams; for the evening pressing belongs to the.Âdityas, and cows are after the manner of the Âdityas; whence this milk of cows is of a fourfold nature: therefore he draws the Âgrayana from four streams.