Garudapurana 1.99.25

1.99.25

vācyatāminyanujñātaḥ pitṛbhyaśca svadhocyatām /
viprairastu svadhetyukto bhūmau siñcettato jalam //

Permitted with 'Let it be spoken', he says 'Let svadhā be spoken to the ancestors'. / Being told by the brāhmaṇas 'Let there be svadhā', he should then sprinkle water on the ground.