>>> "JMM" == Juan Manuel Macías <maciaschain@posteo.net> writes:

> Uwe Brauer <oub@mat.ucm.es> writes:
>> That is odd (maybe my org version is a bit rusty (master june 2020)

> It's strange...

> It should work fine for you (as long as you set
> `org-export-allow-bind-keywords' as non-nil)

Aha, indeed it was nil! I was not even aware of this variable, after
switching to t, your code worked. Thanks because it save me the hassle
to add manually 
#+attr_latex

On the other hand it is good to know that booth solution exits.

Thanks

Uwe