A Rotation Invariant Filter for Two-Dimensional String Matching.

Kimmo Fredriksson Esko Ukkonen A Rotation Invariant Filter for Two-Dimensional String Matching. 118-125 1998 conf/cpm/1998 CPM db/conf/cpm/cpm98.html#FredrikssonU98 http://dx.doi.org/10.1007/BFb0030785