ARTICLE 15
Independent Personal Services
(1) The income generated by a resident of a Contracting State from independent professions or other similar independent activities shall be taxable only in such State unless If he/she regularly operates a fixed base in the other Contracting State for the purposes of carrying out his activities, in such case the income may be taxed in the other Contracting State but only to the extent that it accrues to the resident in that fixed base.
(2) The term "independent personal services" shall include in particular the scientific, literary or educational independent activities as well as the independent activities related to physicians, lawyers, engineers, architects, dentists and accountants.