Postal services [documento electrónico] : quality of service: measurement of loss of registered mail and other types of postal service using a track and trace system: EN 14137: September 2003 / European Committee for Standardization
Postal services [documento electrónico] : address databases: part 1: components of postal addresses: EN 14142-1: February 2003 / European Committee for Standardization
EN 45020 : 1998 : standardization and related activities
EN 50065 -1 : July 1991: signalling on low-voltage electrical installations in the frequency range 3khz to 148,5 khz: part 1: general requirements, frequency bands and electromagnetic disturbances / European Committee for Electrotechnical Standardization