Règle correspondante
Practice Relating to Rule 106. Conditions for Prisoner-of-War Status
Section A. Distinction from the civilian population
Sweden’s IHL Manual (1991) states:
The basic rule for the conduct of combatants is that they are obliged to distinguish themselves from the civilian population when taking part in an attack or in a military operation in preparation for an attack. For combatants belonging to regular forces, this is no problem, since they are recognizable by their uniforms and normally also by the carrying of weapons. 
Sweden, International Humanitarian Law in Armed Conflict, with reference to the Swedish Total Defence System, Swedish Ministry of Defence, January 1991, Section, p. 36.