S., Sivakumar, and Banupriya K. 2017. “A Retrospective Observational Comparative Study of VDRL Vs. TPHA and Their Role in Serodiagnosis of Syphilis in a Tertiary Care Centre”. International Journal of Research in Dermatology 3 (3):444-47. https://doi.org/10.18203/issn.2455-4529.IntJResDermatol20173122.