ITU-T Recommendation E.121 Series E: Overall network operation, telephone service, service operation and human factors. International …– General provisions concerning users. Pictograms, symbols and icons to assist users of the telephone and telefax ...

ITU-T Recommendation E.120 Telephone network and ISDN. Operation, numbering, routing and mobile service. Instructions for users of the international telephone service ITU-T Recommendation E.118 Series E: Overall network operation, telephone service, service operation and human factors. International operation – General provisions concerning Administrations. The international telecommunications charge card ITU-T Recommendation E.117 Telephone network and ISDN. Operation, numbering, routing and mobile service. Terminal devices used in connection with the public telephone service (other than telephones) Рекомендация МСЭ-Т Е.121 Серия Е: Общая эксплуатация сети, телефонная служба, функционирование служб и человеческие факторы. Международная эксплуатация – Общие положения, касающиеся пользователей. Пиктограммы, символы и графические знаки в помощь ... ITU-T Recommendation E.122 Telephone network and ISDN. Operation, numbering, routing and mobile service. Measures to reduce customer difficulties in the international telephone service ITU-T Recommendation E.123 Series E: Overall network operation, telephone service, service operation and human factors… General provisions concerning users. Notation for national and international telephone numbers, e-mail addresses and Web addresses