Income from immovable property may be taxed only in the State where the property is situated under the treaty. Income from immovable property is taxable only in the Contracting State where the property is situated. 'Immovable property' is defined by the law and usage of that State and includes accessories to land, agricultural and forestry livestock and equipment, rights subject to landed property law, usufructs, and rights to payments for working or rights to work mineral deposits, oilwells, quarries and other extraction sites; ships and aircraft are excluded. The rule applies to income from direct use, letting or other use, and to enterprise income and income used in professional services.