BYSTRÖM , P. ., BJÖRKEGREN , K. ., LARSSON , A. ., JOHANSSON , L. ., & 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), 160–164. https://doi.org/10.1080/03009730903027172