Hoeven, C., Robert, A., Derwael, C., Fesler, R., Brasseur, LA., & Brohet, C. (1986). The Normal Pediatric Frank Orthogonal Electrocardiogram - Influence of Weight, Height and Chest Circumference. Journal of Electrocardiology, 19(1), 15-21. https://doi.org/10.1016/S0022-0736(86)80003-6 (Original work published 1986)