Соответствующая норма
Practice Relating to Rule 107. Spies
Section B. Status of spies
The Hellenic Navy’s International Law Manual (1995) provides: “[Spies] can not benefit from the status of prisoner of war and may be tried and convicted even to death.” 
Greece, International Law Manual, Hellenic Navy General Staff, Directorate A2, Division IV, 1995, Chapter 5, § 6.