MONO91 Indexes Compiled by Machine chapter Mary Elizabeth Stevens National Bureau of Standards while not using a citation index as such, makes use of a supplementary citation tracing technique both to shorten manual search time through abstract journals and to follow up additional search leads (Lykoudis, et al, 1959 [387]; Cezairhyan, 1962 [107]). The technique is briefly described as follows: "One starts searching the abstracting journal beginning with the most recent issue and going back through a number of years, a. Next, the bibliographies of the papers located in these a years are searched for new references. The references found in this second step of the search will, in general, cover a period of years (b - a). Then one reverts back to searching through the ab- stracting journal again for another period of a years starting with the year b. This cyclic procedure of alternate searches through the abstracting journal, followed by searching the bibliographies of uncovered papers, is repeated until the total number of desired years of search is covered." 1/ In a sample search on the thermophysical properties of metals, the results showed that the cost of the cyclic procedure was only 65% of the cost of conventional manual search using the abstract journals only. Recent efforts in the development and use of citation indexes proper include experi- ments in evaluation at the American Institute of Physics, [OCRerr]/ an extensive compilation and processing program at the Institute for Scientific Information 3/ and a cooperative pro- gram between the Statistical Techniques Research Group of Princeton University and the Bell Telephone Laboratories (Tukey, 1962 [611] and [6[OCRerr]z[OCRerr]). Reisner has re- ported work on the compilation of a citation index to 30, 000 patent disclosures and its experimental evaluation in progre[OCRerr]s at IBM's Thomas J. Watson Research Center (1963 [497]). Goodman is concerned with a citation index to the literature of new educational media, especially that on programmed learning and teaching machines (1963 [235]). At the Centre d'Etudes Nucleaires de Saclay, a citation index to papers in the field of thermonuclear fusion and plasma physics is being prepared 4/ Lipetz is carrying on work in the preparation and evaluation of citation indexes, begun at the Itek Corporation, as an independent worker and consultant to the A. I. P. project. 5i Carroll and Summit report that citation indexing is under consideration at Lockheed's Missile and Space Division, (1962 [102]). Kessler and associates at M.I.T. 6/ and Salton's group at `I Lykoudis et al, 1959 [387], abstract, p. 351. 2/ 3/ 4/ 5/ 6/ Atherton and Yovich, 1962 [26]; National Science Foundation's CR&D Report No. 11, p. 12. Ibid, pp. 27-28. Ibid, p. 76. Ibid, p. 181. Ibid, p. 128. 34