Copyright problem removed This article has been revised as part of a large scale clean up project of multiple article copyright infringement See the investigation subpage Prior content in this article duplicated one or more previously published sources Copied or closely paraphrased material has been rewritten or removed and must not be restored unless it is duly released under a compatible license For more information please see using copyrighted works from others if you are not the copyright holder of this material or donating copyrighted materials if you are For legal reasons we can not accept copyrighted text or images borrowed from other web sites or published material such additions will be deleted Contributors may use copyrighted publications as a source of information and if allowed under fair use may copy sentences and phrases provided they are included in quotation marks and referenced properly The material may also be rewritten providing it does not infringe on the copyright of the original or plagiarize from that source Therefore such paraphrased portions must provide their source Please see our guideline on non free text for how to properly implement limited quotations of copyrighted text Wikipedia takes copyright violations very seriously and persistent violators will be blocked from editing While we appreciate contributions we must require all contributors to understand and comply with these policies Thank you