Telecontrol equipment and systems - Part 5: Transmission protocols; section 1: Transmission frame formats (IEC 60870-5-1:1990); German version EN 60870-5-1:1993— 39 стр.
Information technology - Open Systems Interconnection - Part 1: Basic Reference Model: The Basic Model (ISO/IEC 7498-1:1994); English version EN ISO/IEC 7498-1:1995