COPELAND, G D Clinical evaluation of a new esophageal electrode, with particular reference to the bipolar esophageal electrocardiogram. I. Normal sinus mechanism. [electronic resource] - American heart journal Jun 1959 - 862-73 p. digital Publication Type: Journal Article ISSN: 0002-8703 Standard No.: 10.1016/0002-8703(59)90295-9 doi Subjects--Topical Terms: Bipolar DisorderElectrocardiographyElectrodesHumans