الإتاحة: https://doi.org/10.1016/j.spl.2011.08.007Testhttps://api.elsevier.com/content/article/PII:S0167715211002719?httpAccept=text/xmlTesthttps://api.elsevier.com/content/article/PII:S0167715211002719?httpAccept=text/plainTest
الإتاحة: https://doi.org/10.1016/j.spl.2011.08.007Testhttp://hdl.handle.net/11336/14907Test
الإتاحة: http://hdl.handle.net/11336/14907Test
الإتاحة: http://www.sciencedirect.com/science/article/pii/S0167715211002719Test