- Collective Security (with E. de Wet)

 

- Committee of Legal Advisers on Public International Law (CAHDI) (with M. Requena)

 

- Codification and Progressive Development of International Law (with O. Sender)

 

- Customary International Law (with O. Sender)

 

- Final Act

 

- Germany, Reunification of (1990) (with J. Hill)

 

- Helsinki Final Act (with D. Purisch)

 

- International Courts and Tribunals, Discontinuance of Cases

 

- International Seabed Authority

 

- Iraq, No-fly Zones

 

- Legal Advisers

 

- North Macedonia (with N. Pavlopoulos)

 

- Peace, Breach of

 

- Peace, Threat to the (with E. de Wet)

 

- State Practice (with O. Sender)

 

- Teachings of the Most Highly Qualified Publicists (Art. 38(1) ICJ Statute)

 

- United Nations Administrative Tribunal, Applications for Review (Advisory Opinions)

 

- United Nations Charter, Enemy State Clauses

 

- United Nations, Security Council

 

- Use of Force, Prohibition of Threat