- Author: Girma Biresaw K.L. Mittal
- Language: English
- Year: 2008
- Author: Girma Biresaw K.L. Mittal
- Language: English
- Year: 2011
- Author: Girma Biresaw, K L Mittal
- Language: English
- Year: 2014
- Author: Girma Biresaw K.L. Mittal
- Language: English
- Year: 2008
- Author: Girma Biresaw K.L. Mittal
- Language: English
- Year: 2008