| In this paper we have constructed some counter examples, showing that Theorem 5.1 and Theorem 5.2 in [2] are incorrect. The fact is that formulas (5.2) and (5.4) in [2] are incorrect, and moreover, the invariant 1's and invariant 0's in Up(R,S) are ignored. We have made a corretion to the two theorems, i. e. Theorem 5.1 and Theorem 5.2 in [2] are correct whenever k = n. |
