Соответствующая норма
Yugoslavia, Socialist Federal Republic of
Practice Relating to Rule 7. The Principle of Distinction between Civilian Objects and Military Objectives
Section D. Attacks against places of civilian concentration, including schools
Under the Socialist Federal Republic of Yugoslavia’s Penal Code (1976), as amended in 2001, it is a war crime to commit or order the commission of “an attack on … a [civilian] settlement”. 
Yugoslavia, Socialist Federal Republic of, Penal Code, as amended in 2001, Article 142(1).