Sotthibundhu, A. ., D. . Buntup, C. . Sanghirun, K. Cherdchu, C. . Cheeramakara, S. . Chansirikarnjan, E. . Nimkulrat, C. . Udommongkol, W. . Wongmek, and W. . Thangnipon. “Low Serum Vitamin B12 in Alzheimerûs Patients As Detected by a Solid Phase Radioimmunoassay”. Siriraj Medical Journal, vol. 60, no. 1, Jan. 2008, pp. 66-68, https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/246322.