DIN ETS 300572:1995 European digital cellular telecommunications system (phase 2) - Unstructured Supplementary Service Data (USSD), stage 3; English version ETS 300572:1995
1995DIN ETS 300572:1995 European digital cellular telecommunications system (phase 2) - Unstructured Supplementary Service Data (USSD), stage 3; English version ETS 300572:1995