Richard Pennycuick wrote:

>...there are non-British holders of knighthoods who do use the title,
>Sir Charles Mackerras being one example

... who together with other well-known examples such as Sir Mohammed Iqbal,
Sir Abubakar Tafawa Balewa, Dame Kiri te Kanawa, Sir Garfield Sobers and
so on all show how citizens of Commonwealth countries are entitled to use
"Sir" or "Dame".

Alan Moss