Kanik-Yüksek, Saliha, et al. “Impact of the Mandatory Hepatitis A Immunization Program: Before and After the Vaccine in Ankara, Central of Turkey”. The Turkish Journal of Pediatrics, vol. 61, no. 5, Oct. 2019, pp. 677-85, https://doi.org/10.24953/turkjped.2019.05.006.