Related Rule
Ecuador
Practice Relating to Rule 8. Definition of Military Objectives
Section G. Economic installations
Ecuador’s Naval Manual (1989) states:
Proper economic targets for naval attack include enemy lines of communication used for military purposes, rail yards, bridges, rolling stock, barges, lighters, industrial installations producing war-fighting products, and power generation plants. Economic targets of the enemy that indirectly but effectively support and sustain the enemy’s war-fighting capability may also be attacked. 
Ecuador, Aspectos Importantes del Derecho Internacional Marítimo que Deben Tener Presente los Comandantes de los Buques, Academia de Guerra Naval, 1989, § 8.1.1.