Kim B. Bruce Angela Schuett Robert van Gent PolyTOIL: A Type-Safe Polymorphic Object-Oriented Language. 27-51 http://link.springer.de/link/service/series/0558/bibs/0952/09520027.htm 1995 conf/ecoop/1995 ECOOP db/conf/ecoop/ecoop95.html#BruceSG95