Just to explain how the citizenship worked in Yugoslavia: one was a citizen of his republic of birth (Serbia in Seleš case), and by that virtue a citizen of Yugoslavian Federation. Taking that analogy, it is not wrong to say that she represented Serbia too, in despite of playing under Yugoslav flag, just like all other sports people of that era. Now that Yugoslavia is no more, her Serbian citizenship still stands, unless she renounced it.
The fact that she was of ethnic Hungarian origin doesn't erase the fact that she was a Serbian and Yugoslavian citizen, born and raised in Serbia.
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