Re: [NTG-context] undefined control sequence bug with German umlaut in bibliography

Well, there *is* more than one way to represent ä in UTF-8

If you mean "non-shortest" forms such as 0xE0 0x83 0xA4 or 0xF0 0x80 0x83 0xA4, then no, they have been forbidden since Unicode 3 in 2000 (formally Corrigendum #1, see http://www.unicode.org/versions/corrigendum1.html). Arthur