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Philippines
Practice Relating to Rule 10. Civilian Objects’ Loss of Protection from Attack
Section B. Situations of doubt as to the character of an object
The Philippine Army Soldier’s Handbook on Human Rights and International Humanitarian Law (2006) notes in its glossary:
Civilian objects – any object which is not a military objective. Objects which are normally civilian objects can, according to the military situation, become military objectives (e.g. house or bridge tactically used by the defender and thus a target for an attacker). In case of doubt whether an object which is normally dedicated to civilian purposes (e.g. a place of worship, a house or dwelling, a school) is a military objective or not, it shall be considered as a civilian object. 
Philippines, Philippine Army Soldier’s Handbook on Human Rights and International Humanitarian Law, A Practical Guide for Internal Security Operations, 2006, p. 67, Glossary.