Tirasak Pasharawipas. (2019) The Crucial Factors of Cobalamin (Vitamin B12) Deficiency in Elderly. Rangsit University:ม.ป.ท.Tirasak Pasharawipas. 2019. The Crucial Factors of Cobalamin (Vitamin B12) Deficiency in Elderly. ม.ป.ท.:Rangsit University;Tirasak Pasharawipas. The Crucial Factors of Cobalamin (Vitamin B12) Deficiency in Elderly. ม.ป.ท.:Rangsit University, 2019. Print.