Bhagavatapurana 9.10.2

9.10.2

tasyāpi bhagavān eṣa sākṣādbrahmamayo hariḥ /
aṃśāṃśena caturdhāgāt putratvaṃ prārthitaḥ suraiḥ /
rāmalakṣmaṇabharata śatrughnā iti saṃjñayā //

2. & 3. Entreated by the gods the glorious Hari, Perfect Brahman, directly became his son by His amsa of amsas in four forms, under the names of Rama, Lakshmana, Bharata and Satrughna and his work and deeds (history), O king, are listened to, and described, by sages who have realised the truth; the (glorious) history of Sita's Lord must have been often listened to by thee also.