Śatapatha Brāhmaṇa ("of a hundred paths") 13.6.2.18

13.6.2.18

athāto dakṣiṇānām madhyam prati rāṣṭrasya yadanyadbhūmeśca brāhmaṇasya ca vittātsatpuruṣam prācī digghortudakṣiṇā brahmaṇaḥ pratīcyadhvaryorudīcyudgātustadeva hotṛkā anvābhaktāḥ

Now as to the sacrificial fees. What there is towards the middle of the kingdom other than the land and the property of the Brâhmana, but including the men, of that the eastern quarter belongs to the Hotri, the southern to the Brahman, the western to the Adhvaryu, and the northern to the Udgâtri; and the Hotrikas share this along with them.