Shipping and air transport profits taxable only in the enterprise's residence, covering rentals, container income and pool participation. Profits from operating ships and aircraft in international traffic are taxable only in the enterprise's State of residence, including rental income and incidental container income, profits from participation in pools or joint businesses, and interest connected with such operations which is treated as operational income rather than subject to the separate interest provision; 'operation' covers transportation of passengers, mail, livestock or goods, ticket sales, incidental leasing and other activities directly connected with such transportation.