Соответствующая норма
Yugoslavia, Socialist Federal Republic of
Practice Relating to Rule 37. Open Towns and Non-Defended Localities
Section C. Attacks on open towns and non-defended localities
The Socialist Federal Republic of Yugoslavia’s Military Manual (1988) prohibits attacks against open towns and non-defended localities. 
Yugoslavia, Socialist Federal Republic, Propisi o Primeri Pravila Medjunarodnog Ratnog Prava u Oruzanim Snagama SFRJ, PrU-2, Savezni Sekretarijat za Narodnu Odbranu (Pravna Uprava), 1988, §§ 77 and 81.
Under the Socialist Federal Republic of Yugoslavia’s Penal Code (1976), as amended in 2001, “indiscriminate attacks on … non-defended localities” are a war crime. 
Yugoslavia, Socialist Federal Republic, Penal Code as amended, 1976, Article 142(2).
In a footnote related to the “use of prohibited means of combat”, the Code further provides that “the following methods of combat are banned under international law: … bombing and other forms of attacks on non-defended towns, villages and other localities and buildings”. 
Yugoslavia, Socialist Federal Republic, Penal Code, 1976, as amended in 2001, Commentary on Article 148(1)(a).