Oksuz, M., and E. Yilmaz. “C677T Methylenetetrahydrofolate Reductase Polymorphism, Folate and Homocysteine Levels and the Risk of Colorectal Cancer”. Annals of Medical Research, vol. 28, no. 9, Sept. 2021, pp. 1620-5, http://www.annalsmedres.org/index.php/aomr/article/view/3897.