Pulastya begot in his wife, Havirbhū, one son of the name Agastya, who in his next birth became Dahrāgni. Besides him, Pulastya begot another very great and saintly son, whose name was Viśravā.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
पुलस्त्योऽजनयत्पत्न्यामगस्त्यं च हविर्भुवि । सोऽन्यजन्मनि दह्राग्निर्विश्रवाश्च महातपाः
pulastyo'janayatpatnyāmagastyaṃ ca havirbhuvi | so'nyajanmani dahrāgnirviśravāśca mahātapāḥ
SB 4.1.36