Felix Polyakov Eran Stark Rotem Drori Moshe Abeles Tamar Flash Parabolic movement primitives and cortical states: merging optimality with geometric invariance. 159-184 2009 100 Biological Cybernetics 2 http://dx.doi.org/10.1007/s00422-008-0287-0 db/journals/bc/bc100.html#PolyakovSDAF09