Thamjamrassri, Thanyalak. 2018. “Low-dose Spinal Bupivacaine decreases the Incidence of Postoperative Urinary Retention after Anorectal Surgery”. Thai Journal of Anesthesiology 44 (1):30-35. https://he02.tci-thaijo.org/index.php/anesthai/article/view/121104.