Taxation of shipping profits: source state may tax foreign-operator income with a mandated reduction and capped rate. Profits from operating ships in international traffic are taxable in the State of the enterprise, while the source State may tax those profits under its domestic law provided the tax imposed is reduced and capped so it does not exceed the lowest rate applicable to comparable profits of a resident of a third State; the rule also covers participation in a pool, joint business or international operating agency.