September 18, 2006: http://www.genesdev.org.floyd.lib.umn.edu/cgi/reprint/20/3/297

October 11, 2006: http://pathogens.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.ppat.0020063

November 8, 2006: http://www.jneurosci.org/cgi/reprint/25/46/10637

January 30, 2007: http://www.sciencemag.org.floyd.lib.umn.edu/cgi/content/full/297/5582/851

March 20, 2007: http://heart.bmj.com.floyd.lib.umn.edu/cgi/reprint/92/8/1172