Ebeling Barbier Charlotte, Johansson Lars, Lind Lars, Ahlström Håkan, and Bjerner Tomas. 2011. “Several Sources of Error in Estimation of Left Ventricular Mass With M-Mode Echocardiography in Elderly Subjects”. Upsala Journal of Medical Sciences 116 (4):258–264. https://doi.org/10.3109/03009734.2011.596586.