\xymatrix @=9pt { A(X') \ar[rr] \ar[dd] \ar[dr] && A(\Delta[n]) \arfib'[d][dd] \arwe[dr] & \\ & C^\ast(X') \ar[rr] \ar[dd] && C^\ast(\Delta[n]) \arfib[dd] \\ A(X) \ar'[r][rr] \arwe[dr] && A(\del\Delta[n]) \arwe[dr] & \\ & C^\ast(X) \ar[rr] && C^\ast(\del\Delta[n]) }