| 1 | |
| Researcher: | Raja Ratnam, S |
| University: | Andhra University |
| Language: | English |
| 2 | |
| Researcher: | Ratnam, Jeetika S |
| Guide: | Singh, Kamal |
| University: | Rashtrasant Tukadoji Maharaj Nagpur University |
| Language: | English |
| 3 | Studies on the colour centres and allied properties of calcium fluoride |
| Researcher: | Ratnam, Vangaveti Venkata |
| University: | Indian Institute of Technology |
| Language: | English |
| 4 | |
| Researcher: | Raja Ratnam, Sri Rangam |
| Guide: | Sriramarao, M |
| University: | Andhra University |
| Language: | English |