Authors: Gary Egan; Tim Silk; Frank Zamarripa; John Williams; Paolo Federico; Ross Cunnington; Leonie Carabott; John Blair-West; Robert Shade; Michael McKinley; Michael Farrell; Jack Lancaster; Graeme Jackson; Peter Fox; Derek Denton Journal: Proc Natl Acad Sci U S A Date: 2003-12-01 Impact factor: 11.205