reference in pdf output of beamer > closing paranthesis not colored

[Wolfgang Engelmann]

Am 15.01.20 um 18:43 schrieb Jürgen Spitzmüller:
> Am Mittwoch, den 15.01.2020, 18:04 +0100 schrieb Wolfgang Engelmann:
>> Thanks, Jürgen. There was no graphic.
> In the file you originally sent, there were several graphics.
>
>> I send the lyx-, bib- and bst style file
>>
>> my pdf output gives Roenneberg et al (2019) all in green except the
>> closing paranthesis )
> This is a problem in the hyperref code with natbib used in beamer.
> Fixing this requires delving deeply into the code. I suggest you ask on
> stackexchange for help.
>
> Jürgen
>
Thanks, Jürgen. I will try another .bst and see. Otherwise following you 
proposal

Wolfgang