H. I. S. Ginting, F. Farhat, and M. I. Sari, “The Serological Examination of Immunoglobulin A Anti-Early Antigen of Epstein–Barr Virus (Anti-EA EBV IgA) in the Nias Tribe Nasopharyngeal Cancer Patients”, Open Access Maced J Med Sci, vol. 10, no. A, pp. 1116–1120, Jul. 2022.