Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 3: Vālmīki Composes the Rāmāyaṇa
Text 1.3.9

स यथा कथितं पूर्वं नारदेन महर्षिणा।
रघुवंशस्य चरितं चकार भगवानृषिः॥

sa yathā kathitaṁ pūrvaṁ nāradena maha-rṣiṇā
raghu-vaṁśasya caritaṁ cakāra bhagavān ṛṣiḥ

saḥ = he; yathā = just as; kathitam purvam = was taught; nāradena = by Nārada; mahā-ṛṣiṇā = the great sage; raghu-vaṁśasya = of Śrī Rāma, who had appeared in the dynasty of Raghu; caritam = a book describing the activities; cakāra = composed; bhagavān = the powerful; ṛṣiḥ = sage.

The powerful sage composed a book that described the activities of Śrī Rāma who had appeared in the dynasty of Raghu just as he was taught by the great sage Nārada.