الوصول الحر: https://doaj.org/article/149c90b4861744ab888bc1d20b2063c5Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::89efdc9cc07e2e16e67a51f89d01e159Testhttps://doi.org/10.1186/s13063-019-3682-zTest
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9699ea399c1ace5ba78c11335bcb6779Testhttps://pubmed.ncbi.nlm.nih.gov/25370364Test