Buppasiri, Pranom, and Sarayoot Chaisitt. 2013. “Incidence of Positive VDRL in the Second Antenatal Screening for Syphilis at Srinagarind Hospital, Khon Kaen University”. Srinagarind Medical Journal 24 (4):292-95. https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/13036.