%0 Journal Article %A S R Jain %A J Lindahl %T Apex cardiogram and systolic time intervals in acute myocardial infarction. %D 1971 %R 10.1136/hrt.33.4.578 %J British Heart Journal %P 578-584 %V 33 %N 4 %U https://heart.bmj.com/content/heartjnl/33/4/578.full.pdf