“Determination Of Cardiac Vector Magnitude And Angle In The 4 Quadrant Graph Using Cardiac Vector Theory”. African Journal of Biomedical Research 27, no. 4S (December 10, 2024): 6320–6328. Accessed October 25, 2025. https://africanjournalofbiomedicalresearch.com/index.php/AJBR/article/view/4776.