Tax exemption for visiting professors and researchers: host-state tax relief for teaching and public interest research for a limited period. A visiting professor, teacher or research scholar who was resident in one Contracting State immediately before visiting the other State to teach or undertake research at a university, college or similar approved institution is exempt from tax in the host State on remuneration for such teaching or research for a limited period; research income is covered only if the work is undertaken in the public interest and not primarily for private benefit.