 The transcription mentioned above is generally used for airplane tickets etc., but sometimes (like in US visas) also simple vowels are used (MULLER, GOSSMANN).The three possible spelling variants of the same name (e.g.Müller / Mueller / Muller) in different documents sometimes lead to confusion, and the use of two different spellings within the same document (like in the passport) may give people who are unfamiliar with the German orthography the impression that the document is a forgery.