1. Vitamin A deficiency disorders in children and women;West;Food Nutr Bull,2003
2. Retinoids in embryonal development;Ross;Physiol Rev,2000
3. Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995-2011: a systematic analysis of population-representative data;Stevens;Lancet Glob Health,2013
4. Vitamin A: biomarkers of nutrition for development;Tanumihardjo;Am J Clin Nutr,2011
5. World Health Organization. Serum retinol concentrations for determining the prevalence of vitamin A deficiency in populations.Geneva (Switzerland): World Health Organization; 2011 [cited 2015 Jan 27]. Available from: http://www.who.int/vmnis/indicators/retinol.pdf.