3 items -- Matrex Tematrex 40 and Termatrex 15, sales brochure, Specifications sheets, Alpha Matrex Indexing Machine.
Documentation Incorporated, Washington D.C., no date, circa 1955-1965; Specialists in Basic and Applied Information Theory, developers of The UNITERM system of coordinate indexing, RADEX Random Fileing Cards, Matrex Indexing Machines.