الوصول الحر: https://escholarship.org/uc/item/8kq929qxTest
الوصول الحر: https://escholarship.org/uc/item/3dp4w5g0Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6c236f31af1af04cbc2e2ac421a2ddc5Testhttp://www.scopus.com/inward/record.url?eid=2-s2.0-84988039530&partnerID=MN8TOARSTest