الوصول الحر: https://doaj.org/article/998c906f377c4ccfbe9e5d7cb030d093Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0f1626f7fa747cb42412f1e2ccdaf771Testhttp://www.sciencedirect.com/science/article/pii/S1013905220307756Test