| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Natural Resources, Conflict, and Sustainable Development | 978-0-415-75450-7 (0-415-75450-X) | 2014 | Okechukwu Ukaga · Ibaba Samuel Ibaba |
| Natural Resources, Conflict, and Sustainable Development: Lessons from the Niger Delta | 978-0-415-80691-6 (0-415-80691-7) | 2012 | Okechukwu Ukaga · Ibaba Samuel Ibaba |