The English version of Atlantis knows how to work with English, French, German, and Spanish ordinals.
You could use this dialog to add support for ordinals of another language. So Atlantis would know which ordinals in that language are valid.
You should specify the valid terminating parts of ordinals of the desired language.
For the example, the list English ordinals looks in this way:
0th
11th
12th
13th
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
Any valid English ordinal is terminated with one of the above strings.
You should construct a similar list of strings for the desired language in order to add support for ordinals of the desired language. Your list might contain a smaller or a greater number of items.
You should not add items corresponding to Roman ordinals. They are built by Atlantis automatically.
Click here for a list of ordinal strings used by Atlantis for the French language.
See also...