1. WHO. Global nutrition targets 2025:policy brief series (WHO/NHM/NHD/14.2).Geneva : World Health Organization;2014
2. WHO. Global nutrition targets 2025: Anemia policy brief (WHO/NHM/NHD/14.4).Geneva : World Health Organization;2014
3. World Health Organization, Haemoglobin Colour Scale: Practical Answer to a vital Need, Department of Blood Safety and Clinical Technology, WHO, Geneva, Switzerland, 2001.
4. H. Ranganathan and N. Gunasekaran, “Simple Method for Estimation of Hemoglobin in Human Blood Using Color Analysis,” IEEE Transactions on Information Technology In Biomedicine, Vol. 10, No. 4, October 2006 657
5. J.Todd Kuenster, “Method for noninvasive (in-vivo) total hemoglobin, oxyhemoglobin, deoxy hemoglobin, carbooxy hemoglobin and methemoglobin concentration determination,” United State Patent , , US patent 5,692,503, issued, Dec. 2,1997