Tsung, Pei-Nan, and Yehuda G. Laor. “General Equations for the Calculations of Biologic Effect Ratios for Parallel Opposing Fields”. Acta Oncologica 17, no. 3 (January 1, 1978): 218–224. Accessed May 19, 2026. https://medicaljournalssweden.se/actaoncologica/article/view/34196.