Treaties and other international acts series. 5501. Double taxation, taxes on income, agreement between United States and United Kingdom of Great Britain and Northern Ireland, relating to Continued application to Southern Rhodesia, Northern Rhodesia, and Nyasaland of convention of Apr. 16, 1945, as modified, effected by exchange of notes signed Washington Dec. 31, 1983; [entered into force Dec. 31, 1963].