Riccardo Poli Nicholas Freitag McPhee Luca Citi Ellery Fussell Crane Memory with Memory in Tree-Based Genetic Programming. 25-36 2009 EuroGP http://dx.doi.org/10.1007/978-3-642-01181-8_3 conf/eurogp/2009 db/conf/eurogp/eurogp2009.html#PoliMCC09