Taxation of artistes and athletes: taxable in the state of performance unless visit is funded from the other state's public funds. Income of public entertainers and athletes from their personal activities is taxable only in the Contracting State where the activities are exercised, but such income is not taxable there if the visit is directly or indirectly supported, wholly or substantially, from public funds of the other Contracting State; 'public funds' means funds of a Contracting State, its political sub divisions, or local or statutory authorities.