Original: K.A. Nilakanta Sastri , A History of South India , p 157 Under Rajaraja Chola I and his son Rajendra Chola I , the dynasty became a military , economic and cultural power in South Asia and South-east Asia .
Simplified: Under Rajaraja Chola I ( Rajaraja the Great ) and his son Rajendra Chola , the dynasty became a military , economic and cultural power in Asia .