Urusopon, K., J. . Roongruangchai, and K. Pilakasiri. “Intradural Communication of L3 and L4 Ventral Nerve Rootlets of Spinal Nerves”. Siriraj Medical Journal, vol. 56, no. 3, Mar. 2004, pp. 111-6, https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/245498.