ARTICLE 21
Teachers, Students and Researchers
(1) Payments which a student or business apprentice who is a resident of a Contracting State and who is present in the other Contracting State solely for the purpose of his education or training receives for the purpose of his maintenance, education or training shall not be taxed in that other Contracting State, provided that such payments arise from sources outside that other State.
(2) Likewise, remuneration received by a teacher or by an instructor who is a resident of a Contracting State and who is present in the other Contracting State for the purpose of teaching or engaging in scientific research at a university, college, school or educational institution or scientific research institution accredited by the government of the first-mentioned Contracting State for a period or periods not exceeding two years shall be exempted from tax in that other Contracting State, provided that such payments arise from sources outside that other State.
This paragraph shall not apply to remuneration and income from research if such research is undertaken for persons and enterprises with business purposes.