الوصول الحر: https://doaj.org/article/5953625d19df451c92d9d536897b968bTest
الوصول الحر: https://doaj.org/article/a94cf8b5a3094e228f5cacd6e0181b41Test
الوصول الحر: https://doaj.org/article/a2b449b2c93f4f098fa48c92d01b2229Test
الوصول الحر: https://doaj.org/article/941003d27c39414f9fe93eb94db8fb21Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::69e26481fc15cce930948a730a057e82Testhttp://europepmc.org/articles/PMC6047600Test