Max Schäfer Mathieu Verbaere Torbjörn Ekman Oege de Moor Stepping Stones over the Refactoring Rubicon. 369-393 2009 ECOOP http://dx.doi.org/10.1007/978-3-642-03013-0_17 conf/ecoop/2009 db/conf/ecoop/ecoop2009.html#SchaferVEM09