The hybrid BCI - Pfurtscheller, Gert; Allison, Brendan Z.; Bauernfeind, Günther; Brunner, Clemens; Solis Escalante, Teodoro; Scherer, Reinhold; Zander, Thorsten O.; Mueller-Putz, Gernot; Neuper, Christa; Birbaumer, Niels (Frontiers in Neuroscience, 2010)