title: THE EFFECT OF THE HEART'S POSITION ON THE ELECTROCARDIOGRAPHIC APPEARANCE OF VENTRICULAR EXTRASYSTOLES.
authors.affiliation: Cardiovascular Laboratory of the Department of Physiology, Michael Reese Hospital, Chicago.
authors.forename: L N
authors.initials: LN
authors.lastname: Katz
authors.forename: W
authors.initials: W
authors.lastname: Ackerman