1. Bentley, J., Little Languages, in regular feature Programming Pearls, Communications of the ACM, Vol. 29, No. 8, August 1986.
2. Darwen, H., Planned UK Contributions to SQL/Temporal, December 17, 1996. (ISO/IEC JTC1/SC21/WG3 DBL MAD-221)
3. Melton, J. (ed), (ISO Working Draft) Temporal (SQL/Temporal), July, 1996. (ISO/IEC JTC1/SC21/WG3 DBL MCI-012)
4. Snodgrass, R.T., Response to MAD-220, January 1997. (ISO/IEC JTC1/SC21/WG3 DBL MAD-245)
5. Snodgrass, R.T., M.H. Böhlen, C.S. Jensen and A. Steiner, Adding Valid Time to SQL/Temporal, 1996. (ISO/IEC JTC1/SC21/WG3 DBLMAD-146r2)