BYSTRÖM PER, BJÖRKEGREN KARIN, LARSSON ANDERS, JOHANSSON LINDA, and BERGLUND ÅKE. 2009. “Serum Vitamin B12 and Folate Status Among Patients With Chemotherapy Treatment for Advanced Colorectal Cancer”. Upsala Journal of Medical Sciences 114 (3):160-64. https://doi.org/10.1080/03009730903027172.