The CCITT, considering that the Recommendation cited in [1] defines International Telegraph Alphabet No.2 (ITA2), which is used, for example, in the international telex service; that International Alphabet No. 5 (IA5), defined in Recommendation T.50 [2], has been established jointly by the CCITT and the International Organization for Standardization (ISO) for use in data transmission (for example); that rules for converting from ITA2 to IA5 and vice versa are desirable to facilitate interworking, for example between terminals in the international telex service and terminals in data networks.
ITU-T S.18 SPANISH-1988 Referenced Document
ITU-T F.1 Operational Provisions for the International Public Telegram Service - Series F: Non-Telephone Telecommunication Services - Telegraph Service - Operating Methods for the International Public Telegram Service Study Group 2; 65 pp*， 1998-03-01 Update
ITU-T T.50 International Reference Alphabet (IRA) (Formerly International Alphabet No. 5 or IA5) Information Technology - 7-Bit Coded Character Set for Information Interchange (Study Group VIII) 22 pp*， 1992-09-01 Update
ITU-T S.18 SPANISH-1988 history
1988ITU-T S.18 SPANISH-1988 CONVERSION BETWEEN INTERNATIONAL TELEGRAPH ALPHABET No. 2 AND INTERNATIONAL ALPHABET No. 5