Sotthibundhu, A., Buntup, D., Sanghirun, C., Cherdchu, K., Cheeramakara, C., Chansirikarnjan, S., Nimkulrat, E., Udommongkol, C., Wongmek, W. and Thangnipon, W. (2008) “Low Serum Vitamin B12 in Alzheimerûs Patients as Detected by a Solid Phase Radioimmunoassay”, Siriraj Medical Journal, 60(2), pp. 66–68. available at: https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/246358 (accessed: 17 September 2026).