Diggelmann, O. The Periodization of the History of International Law: Oliver Diggelmann. The Oxford handbook of the history of international law.(2012).

Diggelmann, Oliver. "The Periodization of the History of International Law: Oliver Diggelmann." The Oxford Handbook of the History of International Law.(2012) .

Diggelmann, Oliver. "The Periodization of the History of International Law: Oliver Diggelmann." The Oxford Handbook of the History of International Law.(2012), .