References :
1.Mayo-Wilson E, Imdad A, Herzer K, Yakoob MY, Bhutta ZA. Vitamin A supplements for preventing mortality, illness, and blindness in children aged under 5: systematic review and meta-analysis. BMJ. 2011 Aug 25;343:d5094. http://www.ncbi.nlm.nih.gov/pubmed/21868478
2.Arrieta AC, Zaleska M, Stutman HR, Marks MI. Vitamin A levels in children with measles in Long Beach, California. J Pediatr. 1992 Jul;121(1):75-8. http://www.ncbi.nlm.nih.gov/pubmed/1625097
3.Fawzi WW, Chalmers TC, Herrera MG, Mosteller F. Vitamin A supplementation and child mortality. A meta-analysis. JAMA. 1993 Feb 17;269(7):898-903. http://www.ncbi.nlm.nih.gov/pubmed/8426449