Ramayana
इति तं बहु सन्दिश्य मनुः पुत्रं समाधिना । जगाम त्रिदिवं हृष्टो ब्रह्मलोकं सनातनम् ॥ 7-79-11 ॥
Having thus instructed his son at length, Manu, joyful, departed through deep meditation to the third heaven, the eternal world of Brahma.
english translation