The Great Epic of the Bhārata dynasty 13.93.2

13.93.2

bhīṣma uvāca |
avedoktavratāścaiva bhuñjānāḥ kāryakāriṇaḥ |
vedokteṣu tu bhuñjānā vrataluptā yudhiṣṭhira || 2 ||

"Bhishma said, 'Let those Brahmanas eat, impelled by desire, who are observant of such vows as are not indicated in the Vedas. As regards those Brahmanas, however, that are observant of such vows are indicated in the Vedas, they are regarded as guilty of a breach of their vow, O Yudhishthira, by eating the Havi of a Sraddha at the request of him who performs the Sraddha.'