boxed extra rehersal mark

[Neuro]

Excuse me, I am almost newbie...

I have a quick small question here:

How do you mark a extra "boxed" rehersal mark such as "A1" ?

My script goes like this:

\mark \default    %% supposse this is "boxed A"
\mark "A1"        %% supposse this is A1, bu I prefer "boxed A1"
\mark "A2"        %% supposse this is A2 ...
\mark "A3"        %% supposse this is A3 ...
\mark \default    %% supposse this is "boxed B"


thank you very much


Neuro
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