الوصول الحر: https://doaj.org/article/f971cfeae52948c395c7c74b61d08a91Test
الإتاحة: https://doi.org/10.1590/S0037-86822009000600009Testhttp://repositorio.bc.ufg.br/handle/ri/18166Test
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=od_______608::69fd93e70cd769e7ead38712829b0a22Testhttp://www.scielo.br/scielo.php?script=sci_arttext&pid=S0037-86822009000600009&lng=en&tlng=enTest