1. Ayodhya Inscription of Dana Deva
2. Persepolis, Nakshi Rustam Inscriptions
3. Moga (Taxila copper plate)
4. Junagadh/Gimar Inscription
5. Nasik Prasasti
6. Inscription of Darius I
7. Coins of Satavahanas
8. Coins of Kadphises II
9. Roman Coins
Literary Sources:
1. Puranas
2. Gargi Samhita
3. Harshacharita of Banabhatta
4. Mahabhasyaof Patanjali
5. Brihastkatha of Gunadhya
6. Madhyamika Sutra of Nagaijuna
7. Buddhacharita of Asvaghosha
8. Malavikagnimitra of Kalidasa