DT4162 - DT: Bulgaria: double taxation agreement, Article 13: Professional 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 he has a fixed base regularly available to him in the other Contracting State for the purpose of performing his activities. If he has such a fixed base, the income may be taxed in the other State but only so much of it as is attributable to that fixed base.
   
   
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.