>>I'm wondering if there is official postoffice spelling, which we can use.
>
>I believe this is why there is a Zip Code or Postal Code.
Unfortunately, nobody in Bolivia uses Zip Codes. The cities are just typed. I don't know whether there are many other countries that are in the same situation.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)