الإتاحة: https://doi.org/10.1186/s13601-016-0116-9Testhttps://hdl.handle.net/11370/4c0de007-92cb-4959-baa5-8de90a2b7cd9Testhttps://research.rug.nl/en/publications/4c0de007-92cb-4959-baa5-8de90a2b7cd9Testhttps://pure.rug.nl/ws/files/35544223/art_3A10.1186_2Fs13601_016_0116_9.pdfTest
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::32caf7dc02c99b6a104176dbe08d6b8fTesthttps://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/16687Test
الإتاحة: http://hdl.handle.net/10138/176243Test