1. The EU metric directive (80/181/EEC) COUNCIL DIRECTIVE of 20 December 1979 on the approximation of the laws of the Member States relating to units of measurement and on the repeal of Directive 71/354/EEC (1980L0181 - EN - 09.02.2000 - 003.001 - 1)
2. The EU Medical devices Directive (93/42/EEC) Council Directive 93/42/EEC of 14 June 1993 concerning medical devices, (1993L0042 -EN -11.10.2007- 005.001- 2)
3. ISO 80601-2-13:2011(E) Particular requirements for basic safety and essential performance of an anaesthetic workstation
4. Continuous hemodynamic monitoring by esophageal Doppler;Singer;Crit Care Med,1989
5. Oesophageal Doppler monitoring: should it be routine for high-risk surgical patients?;Singer;Curr Opin Anaesthesiol,2011