Soontrapa, S., Soontrapa, S., Chailurkit, L.-O., Sakondhavat, C., Kaewrudee, S., Somboonporn, W. and Loa-unka, K. 2013. Prevalence of Vitamin D Deficiency among Postmenopausal Women at Srinagarind Hospital, Khon Kaen Province, Thailand. Srinagarind Medical Journal. 21, 1 (Nov. 2013), 23–29.