Ramayana
स तु तत्रावसत्प्रीतो धर्मात्मा नैर्ऋतर्षभः । समुद्रपरिघायां तु लङ्कायां विश्रवात्मजः ॥ 7-3-34 ॥
And that righteous-souled bull among the Nairritas, the son of Vishravas, dwelt there contentedly in Lanka, which has the ocean for its moat.
english translation