Ramayana
तस्मिन्काले महातेजाः प्राजापत्यो महानृषिः । स्वाध्यायमकरोत्तत्र तपसा भावितः स्वयम् ॥ 7-2-16 ॥
At that time the great-splendored son of Prajapati, the mighty sage, exalted by his own austerities, was reciting the Veda there.
english translation