Garudapurana 1.50.10

1.50.10

brāhmaṃ tu mārjanaṃ mantraiḥ kuśaiḥ sodakabindubhiḥ /
āgreyaṃ bhasmanā'pādamastakāddehadhūnanam //

The brāhma bath is sprinkling with mantras using kuśa grass with drops of water; / The āgneya bath is dusting the body with ash from foot to head;