hyperlink syntax for parameters in php-link

[artmusicstudio2]

hello experts,
my hyperlink fronm word =

format:

[http://www.xxxxxx.de/workspace.php?q=nnnnnn&d=210318&p=1&v=1&k=1]


calling a php with parameters.


ok, works.

but:

is there a syntax to include german "ü" into the syntax of "nnnnnnn" ?
the html-substitudes like ü do not work, a simple "+" also is not accepted.

any idea?

thanx
regards
stan