Bernard Haasdonk Alaa Halawani Hans Burkhardt Adjustable Invariant Features by Partial Haar-Integration. 769-774 2004 ICPR (2) http://csdl.computer.org/comp/proceedings/icpr/2004/2128/02/212820769abs.htm db/conf/icpr/icpr2004-2.html#HaasdonkHB04