الإتاحة: https://doi.org/10.1093/cvr/cvw135Testhttp://cardiovascres.oxfordjournals.org/cgi/content/short/111/suppl_1/S16Test
الإتاحة: https://doi.org/10.1136/hrt.2006.100818Testhttp://heart.bmj.com/cgi/content/short/93/10/1231Test
الإتاحة: https://doi.org/10.1136/hrt.2003.031179Testhttp://heart.bmj.com/cgi/content/short/90/9/1009Test