Sutthichon , Ponlawat, and Kijja Jearwattanakanok. 2020. “Treatment Success and Associated Factors in Unknown Stage Syphilis Treated With Standard Regimen in Nakornping Hospital”. Journal of Nakornping Hospital 11 (2). https://he01.tci-thaijo.org/index.php/jnkp/article/view/245233.