Aids for Determining Magnitude and Direction of Electric Axes of the Electrocardiogram
Charles E. Jackson, Travis Winsor · Circulation · 1950
Tables are presented which serve to facilitate the determination of magnitudes and directions of the electrical axes of various waves and segments of the electrocardiogram (P, QRS, RS-T, T and G). The tables may be used with the standard or unipolar limb leads. Normal values for the magnitudes and directions of certain vectors are presented.