Ramayana
तस्य पुत्रद्वयं ब्रह्मन्द्वाभ्यां स्त्रीभ्यामजायत । अहं श्वेत इति ख्यातो यवीयान्सुरथो ऽभवत् ॥ 7-78-4 ॥
To him, O brahmin, two sons were born of two wives: I was the one known as Shveta, and the younger came to be Suratha.
english translation