Independent Personal Services
(1) Income derived by a resident of a Contracting State in respect of professional services or other activities of an independent character shall be taxable only in that State unless such services are performed in the other Contracting State; and:
- (a) the income is attributable to a fixed base which the individual has regularly available to him in that other State; or
- (b) such individual is present in that other State for a period or periods exceeding in the aggregate 183 days in any consecutive twelve-month period.
In such a case the income attributable to the services may be taxed in that other State in accordance with principles similar to those of Article 7 for determining the amount of business profits and attributing business profits to a permanent establishment.
(2) The term "professional services" includes especially independent scientific, literary, artistic, educational or teaching activities as well as the independent activities of physicians, lawyers, engineers, architects, dentists and accountants.