1. C. Date, An Introduction to Database Systems, 7th edition (Addison-Wesley Chapter 22, 2000), pp. 730–768.
2. R. Snodgrass, M. Böhlen, C. Jensen, A. Steiner, Adding Valid Time to SQL/Temporal, SQL/Temporal Change Proposal, ANSI X3H2-96-501r2, ISO/IEC JTC1/SC21/WG3 DBL MAD-146r2, 1996.
3. C. Jensen, Temporal Database Management, PhD, 2000.
4. R. Snodgrass, M. Böhlen, C. Jensen, A. Steiner, Adding Transaction time to SQL/Temporal, SQL/Temporal Change Proposal, ANSI X3H2-96-502r2, ISO/IEC JTC1/SC21/WG3 DBLMAD-147r2, 1996.
5. A. Steiner, A Generalization Approach to temporal Data Models and Their Implementations, PhD, Zurich, 1998.