Subject
- Economic sanctions6
- Education6
- Harbours6
- Marine navigation6
- Air services agreements5
- Conferences5
- Human geography5
- Legislation5
- Military aviation5
- Military intelligence5
- Physical geography5
- Slavery5
- Administration of justice4
- Boats4
- Consumption4
- Desert warfare4
- International relations4
- Peasantry4
- Personnel4
- Petroleum industry4