Atharvaveda 6.98.3

6.98.3

prā́cyā diśás tvám indrāsi rā́jotódīcyā diśó vr̥trahan chatruhó 'si |
yátra yánti srotyā́s táj jitáṃ te dakṣiṇató vr̥ṣabhá eṣi hávyaḥ ||3||

Of the eastern quarter thou, O Indra, art king; also of the northern quarter art thou, O Vritra-slayer, slayer of foes; where the streams go, that is thy conquest; in the south, as bull, thou goest worthy of invocation.