Règle correspondante
Practice Relating to Rule 10. Civilian Objects’ Loss of Protection from Attack
Sweden’s IHL Manual (1991) states:
During military operations it may often be difficult to establish within a short space of time whether property should be classified as a civilian object or a military objective. To avoid meaningless destruction as far as possible, a so-called dubio rule is included in Article 52 [of the 1977 Additional Protocol I]. This states that in case of doubt whether an object which is normally dedicated to civilian purposes is being used in the adversary’s military activity, it shall be presumed that it is not being so used. Among such normally civilian objects are mentioned particularly places of worship, houses and other dwellings, and schools. 
Sweden, International Humanitarian Law in Armed Conflict, with reference to the Swedish Total Defence System, Swedish Ministry of Defence, January 1991, Section, p. 55.