Tapanya, Thorfun, Vipa Boonkiticharoen, and Nakorn Phaisangittisakul. 2015. “Monte Carlo Multiple-source Model for 6 mV Photon Beams from Varian Clinac iX Linear Accelerator”. Research Medical Journal 38 (2):100-110. https://he02.tci-thaijo.org/index.php/ramajournal/article/view/95903.