Omar Helmy, Dina, Mahmoud Tag El-Sabah, Mohamed Sherif Negm, and Mina Armia. “Diagnostic and Pathologic Value of Programmed Death-Ligand 1 Expression in Colon Carcinoma”. Asian Pacific Journal of Cancer Biology 5, no. 4 (December 7, 2020): 159-166. Accessed April 26, 2024. http://waocp.com/journal/index.php/apjcb/article/view/585.