Règle correspondante
Practice Relating to Rule 10. Civilian Objects’ Loss of Protection from Attack
Section B. Situations of doubt as to the character of an object
Croatia’s LOAC Compendium (1991) affirms that in case of doubt as to whether an object is military or civilian in character, it should be considered as a civilian object. 
Croatia, Compendium “Law of Armed Conflicts”, Republic of Croatia, Ministry of Defence, 1991, p. 7.