F<w> := GF(4);
G1 := Matrix(F, 3, 3,[w,0,0,0,w,1,0,1,w]);
C1 := AdditiveCode(GF(2), G1);
G2 := Matrix(F, 3, 3,[w,0,0,0,w,0,0,0,w]);
C2 := AdditiveCode(GF(2), G2);
G3 := Matrix(F, 3, 3,[w,1,1,1,w,0,1,0,w]);
C3 := AdditiveCode(GF(2), G3);