It works perfectly! How about the "". I use this list of sheets as a reference (similar as indirect function in Excel) in the formula:
=[Book1]%(col(A)[i]$)!J1
And if the name is not in "" the formula does not work.
Kind regards,
Dominik
Edit:
SOLVED:
range bk=[book1];
int kk = bk.nlayers;
range sh = [book1]$(kk)!;
range aa = [book2]sheet1!col(1);
string strchar$=char(34)$;
aa[kk]$=strchar$ + sh.name$ + strchar$;