RT Journal Article SR Electronic T1 Assessment of correction formula for echocardiographic estimations of left ventricular volumes. JF British Heart Journal JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 294 OP 296 DO 10.1136/hrt.40.3.294 VO 40 IS 3 A1 M A Martin YR 1978 UL http://heart.bmj.com/content/40/3/294.abstract AB