Facts about NATO / Published by the North Atlantic Treaty Organization ; [pref. by Paul-Henri Spaak] tribune libre Pourquoi l'O.T.A.N.? / Paul-Henri Spaak unsolved problems of European defense / by Henry A. Kissinger uitgave van de atlantische commissie Actuele vraagstukken / door Paul-Henri Spaak Current topics / Paul-Henri Spaak