Garudapurana 1.52.3

1.52.3

brahmahā dvādaśābdāni kuṭīṃ kṛtvā vane vaset /
kuryādanaśanaṃ vātha bhṛgoḥ patanameva ca //

A slayer of a brāhmaṇa should live in the forest for twelve years after building a hut; / or he should practice starvation, or fall from a precipice;