1. ; eds. INTREX, Report of a Planning Conference on Information Transfer Experiments. Cambridge, MA: M. I. T. Press; 1965.
2. ; ; “The User Interface for the Intrex Retrieval System.” In: ed. Interactive Bibliographic Search: The User/Computer Interface. Montvale, NJ: AFIPS Press; 1971: 159–210.
3. Project intrex: A general review
4. Project Intrex Semiannual Activity Reports. Cambridge, MA: Massachusetts Institute of Technology. Issued semiannually from 1966 through 1972 on March 15 and September 15 of each year. NTIS accession numbers for those reports specifically referenced in this paper are (a) 15 March 1970, PB 190369;
5. (b) 15 September 1970, PB 190805;