Torbeyns, JokeDe Smedt, BertPeters, GreetGhesquiere, PolVerschaffel, Lieven2014-01-172014-01-172010http://hdl.handle.net/2003/3183310.17877/DE290R-7739enGesellschaft für Didaktik der Mathematik510Indirect Addition: Theoretical, Methodological and Educational Considerationsconference contribution