ICRC databases on international humanitarian law
Treaties, States Parties and Commentaries
Treaties and Documents
Geneva Conventions of 1949 and Additional Protocols, and their Commentaries
Historical Treaties and Documents
Declaration concerning the Laws of Naval War. London, 26 February 1909.
Chapter I : Blockade in time of war - Art. 2.
Art. 2. In accordance with the Declaration of Paris of 1856, a blockade, in order to be binding, must be effective -- that is to say, it must be maintained by a force sufficient really to prevent access to the enemy coastline.