Hannah

In German, an umlaut signifies an "e" after the vowel it is placed over.

During the war, many German typewriters were not fitted with the umlauten keys, and thus, the "e" after the vowel became standard practice in most writings.

So, to be correct in German, you can always write �¼ as "ue",

�¶ as "oe", and �¤ as "ae".

Not so sure about Swedish, but that's how it works in German.

Hope this helps.