Related Rule
Practice Relating to Rule 8. Definition of Military Objectives
Section G. Economic installations
The Hellenic Navy’s International Law Manual (1995) states with regard to naval bombardment:
1. … [T]he provisions of the otherwise obsolete IX Hague Convention concerning the respect and protection of the victims of armed conflict should be considered as bearing a perpetual binding effect.
2. To the above effect, the significance of the codified text of IX Hague Convention is great and the following provisions should be applied by the belligerents:
c. Bombardment only of targets excluded by the prohibition of art. 1 (military works, military or naval establishments, depots of arms or war material, workshops or plants which could be utilized for the needs of the hostile fleet or army and the ships of war in the harbour) (art. 2). 
Greece, International Law Manual, Hellenic Navy General Staff, Directorate A2, Division IV, 1995, Chapter 7, Part II, §§ 1–2.