Table 1 from The incidence and significance of superior QRS axis in children with cyanotic congenital heart disease. | Semantic Scholar
Determining Axis | Learn the Heart
Understanding the ECG. Part 6: QRS axis | British Journal of Cardiac Nursing
Clinical impact of left and right axis deviations with narrow QRS complex on 3-year outcomes in a hospital-based population in Japan | Scientific Reports
Heart Axis Calculation
Table 4 from The incidence and significance of superior QRS axis in children with cyanotic congenital heart disease. | Semantic Scholar