Règle correspondante
Yugoslavia, Federal Republic of
Practice Relating to Rule 14. Proportionality in Attack
According to the Report on the Practice of the Federal Republic of Yugoslavia, no doubt can be raised about the existence of an opinio juris in favour of the principle of proportionality. The report alleges that serious violations of the principle of proportionality did occur during the conflict in Croatia, for example, during hostilities in Vukovar and Dubrovnik where artillery was massively used, and notes that the press regularly covered this issue in 1991. 
Report on the Practice of the Federal Republic of Yugoslavia, 1997, Chapter 1.5.