Ramayana
एवमुक्तः सुरैर्ब्रह्मा ऽचिन्तयत् पद्मसम्भवः । चिन्तिता चोपतस्थे ऽस्य पार्श्वं देवी सरस्वती ॥ 7-10-41 ॥
Thus addressed by the gods, Brahma the lotus-born reflected; and as he thought of her, the goddess Sarasvati appeared at his side.
english translation