[taejo]

Moreover, in a later picture on the page you can see an example showing a -dóttir name in that field (I had wondered if perhaps it was only used for people who happened to have a "real" surname as opposed to a patronymic, e.g. foreign-born citizens) https://en.m.wikipedia.org/wiki/Icelandic_passport#/media/Fi...

[cyberax]

Facepalm. I don't know how I missed that.