Mahabharata 13.71.1
युधिष्ठिर उवाच · yudhiṣṭhira uvāca
उक्तं वै गोप्रदानं ते नाचिकेतमृषिं प्रतिमाहात्म्यमपि चैवोक्तमुद्देशेन गवां प्रभो
uktaṃ vai gopradānaṃ te nāciketamṛṣiṃ pratimāhātmyamapi caivoktamuddeśena gavāṃ prabho
Our plain-language meaning of this verse is waiting for scholar review.