EN 14012 [documento electrónico] : postal services: quality of service: complaints handling principles / European Commitee for Standardization
CEN/TS 15511 [documento electrónico] : postal services: quality of service: information available on postal services / European Committee for Standardization
CEN/TR 15735 [documento electrónico] : postal services: quality of service: distance to access points / European Committee for Standardization