الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::cd87bc3f4c9ea3dbc4e6316a833cc32aTest
الإتاحة: https://epublications.marquette.edu/theses/1099Testhttps://epublications.marquette.edu/context/theses/article/2098/viewcontent/knepl_e_2005.pdfTest