1. Global Surgery 2030: evidence and solutions for achieving health, welfare, and economic development;Meara;Lancet,2015
2. ISO 18835:2015 Inhalational anaesthesia systems - Draw-over anaesthetic systems http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=62046
3. Universal Anaesthesia Machine Maintenance Manual CE 0120 Doc 1974-005 2013 http://www.frankshospitalworkshop.com/equipment/documents/anaesthesia/service_manuals/Gradian%20UAM%20Anaesthesia%20Machine%20-%20Service%20manual.pdf
4. The patient inflating valve in anaesthesia and resuscitation breathing systems;Fenton;Anaesthesia and Intensive Care,2013
5. ISO 80601-2-13:2011 Medical electrical equipment - Part 2-13: Particular requirements for basic safety and essential performance of an anaesthetic workstation http://www.iso.org/iso/catalogue_detail.htm?csnumber=51285