I find it funny, Turkey was aldready a good test case for handling international users data :), I spend some hours on a bug in json with integer parsing of some users integer inputs in rares cases.

It was because of the way they write/parse integer using dots as separators. (Yes, the real problem was me having forgot to force server and client to use the same locale settings :) )

An old article talking of it : https://blog.codinghorror.com/whats-wrong-with-turkey/