Rikard Berthilsson Anders Heyden Recognition of Planar Point Configurations Using Density of Affine Shape. 72-88 http://link.springer.de/link/service/series/0558/bibs/1406/14060072.htm 1998 conf/eccv/1998-1 ECCV (1) db/conf/eccv/eccv1998-1.html#BerthilssonH98