Symbol,Reference
iso,"[ISO/IEC 11572 (Basic Call) (Information technology -- Telecommunications and information
                 exchange between systems -- Private Integrated Services Network
                 -- Circuit mode bearer services -- Inter-exchange signalling
                 procedures and protocol.)][ISO/IEC 11582 (Generic Functional Protocol) (Information technology -- Telecommunications and information
                 exchange between systems -- Private Integrated Services Network
                 -- Generic functional protocol for the support of supplementary
                 services -- Inter-exchange signalling procedures and protocol.)]"