Hans Schlenker Georg Ringwelski POOC: A Platform for Object-Oriented Constraint Programming. 159-170 2002 conf/colognet/2002 International Workshop on Constraint Solving and Constraint Logic Programming http://dx.doi.org/10.1007/3-540-36607-5_12 db/conf/colognet/colognet2002.html#SchlenkerR02