John D. Holliday Geoffrey M. Downs Valerie J. Gillet Michael F. Lynch Winfried Dethlefsen Evaluation of the screening stages of the Sheffield Research Project on Computer Storage and Retrieval of Generic Chemical Structures in Patents. 39-46 1994 34 Journal of Chemical Information and Computer Sciences 1 http://pubs.acs.org/cgi-bin/archive.cgi/jcisd8/1994/34/i01/f-pdf/f_ci00017a005.pdf db/journals/jcisd/jcisd34.html#HollidayDGLD94