1. Development of an International standard for conformance testing X.25 DTEs;Alfano,1990
2. CCITT Recommendations X.25 1980 and 1984, Interface Between Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE) for Terminals Operating in the Packet Mode and Connected to Public Data Networks by Dedicated Circuit.
3. TTCN status and assessment;Doubet,1989
4. ISO 8208, Information Processing Systems—X.25 Packet Level Protocol for Data Terminal Equipment.
5. ISO/IEC 8882-3 X.25 DTE Conformance Testing—Part 3 Packet Level Conformance Test Suite.