SB 9.10.1
sri-suka uvaca
khatvangad dirghabahus ca
raghus tasmat prthu-sravah
ajas tato maha-rajas
tasmad dasaratho ’bhavat
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sukadeva Gosvami said: The son of Maharaja Khatvanga was Dirghabahu, and his son was the celebrated Maharaja Raghu. From Maharaja Raghu came Aja, and from Aja was born the great personality Maharaja Dasaratha.