Related papers: Non-linear curvature perturbation for general mult…

This paper has been withdrawn by the author due to a crucial sign error in Theorem 3.4.

The paper is withdrawn. The proof has an error and it requires a different approach.

This paper has been withdrawn by the author due to a crucial error related with the consideration of regular points

This paper has been withdrawn due to crucial erros in equations (24)--(31).

The paper has been withdrawn due to a crucial error in section 3.

This article has been withdrawn due to an error in a proof of the main result.

This paper has been withdrawn by the author because there are some typos in proofs.

This paper has been withdrawn by the author, due an error in computing the invariance of the so(4,1) and so(3,2) "inner product."

The paper has been withdrawn by the author.

This paper has been withdrawn by the author, due to obsolete reference [4], insufficient discussion in sec. 4, and major conceptual error in sec. 5.

This paper has been withdrawn by the author, due to errors in Groebner basis calculations in the cases of five and six dimensional groups.

This paper has been withdrawn by the author due to a crucial sign error.

This paper has been withdrawn by the authors due to need of essential revision.

The paper is withdrawn due to some errors.

This paper has been withdrawn by the authors. We have discovered an error in the evaluation of the diagram, which invalidates our conclusion.

This paper has been withdraw by the auhor due to a mistake in classification of the algebra

This paper has been withdrawn by the author because the conclusions reached in it are incorrect.

This paper has been withdrawn by the author due to errors.

This paper has been withdrawn by the author, due to a crucial error in page 5.

This paper has been withdrawn by the author due to a crucial error in the proof of Lemma 2.2.