1.		EN 60835-2-4 /A1 : methods of measurements for equipment used in digital microwave radio transmission systems: part 2: measurements on terrestrial radio-relay systems: section 4: transmitter/receiver including modulator/demodulator: (IEC 835-2-4: 1993 / A1: 1997) / European Commitee for Electrothecnical Standardization Data Publicação: 1997 Tema: Normas
2.		EN 50221 : common interface specification for conditional access and other digital video broadcasting decoder applications / European Commitee for Electrothecnical Standardization Data Publicação: 1997 Tema: Normas