Narapatijayacarya 4.4.5

4.4.5

avakahaḍādiṣu prācyāṃ maṭaparatāśca dakṣiṇe ||
nayabhajakhāśca vāruṇyāṃ gasadacalāstathottare ||

[The phonemes] a, va, ka, ha, and ḍa in the east, ma, ṭa, pa, ra, and ta in the south, / na, ya, bha, ja, and kha in the west, and likewise ga, sa, da, ca, and la in the north.