1. Centers for Disease Control and Prevention Sexually Transmitted Disease Surveillance 2000, 2008-2016 Atlanta, GA U.S. Department of Health and Human Services, Centers for Disease Control and Prevention 2001 2017
2. Seattle and King County Quarterly STD Report 4th Quarter 2016 King County STD Epidemiology Reports https://www.kingcounty.gov/~/media/depts/health/communicable-diseases/documents/hivstd/STD-Report-4Q-2017.ashx?la=en
3. Syphilis ( Treponema pallidum ) 2018 Case Definition https://wwwn.cdc.gov/nndss/conditions/syphilis/case-definition/2018/
4. Otosyphilis: A review of 85 cases;Yimtae;Otolaryngol Head Neck Surg,2007