Presents a database system development model in which theoretical support in the form of automated theorem proving is brought to bear on the problem of enforcing integrity, i.e., ensuring that the database system represents only those states and transitions that are possible in the world it models. (MBR)

Describes an interactive data retrieval system which was designed and implemented for casual users and which incorporates a user-friendly interface, aids to train beginners in use of the system, versatility in output, and error recovery protocols. A 14-item reference list and two figures illustrating system operation and output are included. (JL)