1
Department of Mathematics, Faculty of Science, Assiut University, Assiut 71516, Egypt
2
Department of Mathematics, Faculty of Science, South Valley University, Qena 83523, Egypt
http://dx.doi.org/10.1016/j.joems.2014.02.001
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/ withdrawalpolicy). The authors have plagiarized part of a paper that had already appeared in Afrika Mathematika, 2012, 1–9. http:// dx.doi.org/10.1007/s13370-012-0083-9. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
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