Robert D. Brown Geoffrey M. Downs Gareth Jones Peter Willett 0002 Hyperstructure model for chemical structure handling: Techniques for substructure searching. 47-53 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_ci00017a006.pdf db/journals/jcisd/jcisd34.html#BrownDJW94