الوصول الحر: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1519-69842003000300014Test
الوصول الحر: https://doaj.org/article/4c88dd766a5346edb7c2e01d4f0c3a01Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c988bb95f9253701e2a07fc871c8677cTesthttp://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-69842003000300014Test