Al-dujaili, A. H., W.F. Al-Taei, K. M. Turky, and G. H. Al-Ubaidi. 2017. “Comparative Study of CA19-9 Levels As Tumor Marker in Sera and Tissues of Breast, Prostate and Thyroid Cancer Patients”. Ibn AL-Haitham Journal For Pure and Applied Sciences 22 (1). https://jih.uobaghdad.edu.iq/index.php/j/article/view/1273.