1. ITU-T Recommendation X.210, Information Technology-Open Systems Interaction-Basic Reference Model: Conventions For The Definition of OSI Services, November 1993.
2. ITU-T Recommendation X.214, Information Technology-Open Systems Interconnection-Transport Service Definition, November 1995.
3. AT&T. FSM Library. URL: http://www.research.att.com/sw/tools/fsm .
4. J. Billington. Abstract Specification of the ISO Transport Service Definition using Labelled Numerical Petri Nets. In Protocol Specification, Testing, and Verification, III, pages 173–185. Elsevier Science Publishers, 1983.
5. J. Billington. Formal Specification of Protocols: Protocol Engineering. In Encyclopedia of Microcomputers, pages 299–314. Marcel Dekker, New York, 1991.