Now, I would hope you already know this, as you have been involved in many of these discussions before, but for the benefit of anyone who may actually see the question with no reply and assume PBS is automatically correct without independently looking it up for themselves (I encourage you to do so rather than taking either my or PBS’s word for it). It’s very simple. The alphabet we use is the Latin alphabet. The language this name is from (Serbian) also has a Latin alphabet, meaning that every Serbian name has a specific spelling in the Latin alphabet. For this name, that spelling is “Ana Ivanović”. This information is all available on Wikipedia itself, you can easily look it up. Serbian language, Serbian Latin alphabet, Ana Ivanović’s article in the Latin alphabet on the Serbian Wikipedia. Now, having said the bit about looking it up for yourself, I shall try to avoid answering any more questions that can be definitively answered with quick searches. Find out the relevant facts for yourself, don’t take the word of anyone here.