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This paper has been withdrawn by the author, due to the insecurity against attacks received in quant-ph/0605027v5.

This paper has been withdrawn by the author, due to an error in Proposition 2.2.

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The authors have withdrawn this paper.

This paper has been withdrawn by the author due to a crucial error.

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This paper has been withdrawn by the author(s) due to the discussion was made on the basis of linear term merely, which is incomplete.

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This paper has been withdrawn at the author's request.

This paper has been withdrawn by the author due to rewritting and skipping crucial sign errors.

This paper has been withdrawn by the author due to the paper does not belong to Condensed Matter field.

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This paper has been withdrawn by the author(s), due a crucial error in Eqn. 30.

This paper has been withdrawn by the author due to a crucial errors.

This paper has been withdrawn by the author, due a crucial error in the main idea.

This paper has been withdrawn by the author due to a crucial error.

This paper has been withdrawn by the authors because the paper is largely revised and improved, and to appear in Mechanics Research Communications.

This paper has been withdrawn by the authors, due a oversimplified decoherence model. It will be substituted by a new work.

This paper has been withdrawn by the author.

This paper has been withdrawn by the authors because the results obtained have been reported earlier by other authors.