Martens SMM, Mooij JM, Jeremy Jeremy Hill, Farquhar J, Schölkopf B. A graphical model framework for decoding in the visual ERP-based BCI speller. Neural Comput [Internet]. 2011;23(1):160-82. http://www.ncbi.nlm.nih.gov/pubmed/20964540

Martens SMM, Jeremy Jeremy Hill, Farquhar J, Schölkopf B. Overlap and refractory effects in a brain-computer interface speller based on the visual P300 event-related potential. J Neural Eng [Internet]. 2009;6(2):026003. http://www.ncbi.nlm.nih.gov/pubmed/19255462