الإتاحة: https://doi.org/10.4038/jepsl.v2i1.5734Testhttp://www.sljol.info/index.php/JEPSL/article/view/5734Test
الإتاحة: https://doi.org/10.4038/sjae.v8i0.1826Testhttp://www.sljol.info/index.php/SJAE/article/view/1826Test