| Titel | ISBN-13 (ISBN-10) | Erscheinungsjahr |
|---|---|---|
| Towards Confederation in the Horn of Africa: Focus on Ethiopia and Eritrea | 978-3-88939-876-5 (3-88939-876-6) | 2007 |
| Towards Democracy and Constitutionalism in Africa: Internal Weakness and Unfavourable Global Arena | 978-3-8258-7797-2 (3-8258-7797-3) | 2018 |