The following publications are possibly variants of this publication:
- A Rapidly Extensible Language System (Rel English)Bozena H. Dostert, Frederick B. Thompson. COLING 1969: [doi]
- REL: A Rapidly Extensible Language systemThompson, F. B., Lockemann, P. C., Dostert, B., Deverill, R. S.. In Proceedings of the 1969 24th national conference. 1969: [doi]
- REL: A Rapidly Extensible Language systemFrederick B. Thompson, Peter C. Lockemann, Bozena H. Dostert, R. S. Deverill. acm 1969: 399-417 [doi]
- Practical Natural Language Processing: The REL System as PrototypeFrederick B. Thompson, Bozena Henisz Thompson. ac, 13:109-168, 1975.
- A Rapidly Extensible Language System (The Rel Language Processor)Peter C. Lockemann, Fredrick B. Thompson. COLING 1969: [doi]