Independent personal services: residence-state taxation, with fixed base or prolonged presence allowing source-state taxation. Income from independent personal services of a resident is taxable solely in the State of residence except where the individual has a fixed base in the other Contracting State-only income attributable to that fixed base may be taxed there-or where the individual's stay in the other Contracting State meets the treaty's prolonged-presence threshold, in which case only income from activities performed there may be taxed by that State.