Bar-kodovi, računanje kontrolne 13-te cifre u Excelu
=A2&(ROUNDUP(((MID(A2,2,1)+MID(A2,4,1) +MID(A2,6,1)+MID(A2,8,1)+MID(A2,10,1)+MID(A2,12,1))*3) +(MID(A2,1,1)+MID(A2,3,1)+MID(A2,5,1)+MID(A2,7,1) +MID(A2,9,1)+MID(A2,11,1)),-1)-(((MID(A2,2,1)+MID(A2,4,1) +MID(A2,6,1)+MID(A2,8,1)+MID(A2,10,1)+MID(A2,12,1))*3) +(MID(A2,1,1)+MID(A2,3,1)+MID(A2,5,1)+MID(A2,7,1) +MID(A2,9,1)+MID(A2,11,1))))