1. The Form of the Electrocardiogram. IV. The Mean Electrical Axis and the Center of Stimulation;Wilson,1930
2. A Primer of Electrocardiology;Burch,1945
3. Essentials of Electrocardiography;Ashman,1941
4. Clinical Aspects of the Electrocardiogram;Pardee,1941
5. The Fundamentals of Electrocardiographic Interpretation;Carter,1937