Poulton, Simon W.; Strauss, Harald; Canfield, Donald E.; Narbonne, Guy M.; Ross, Gerry; Goldberg, Tatiana; Knoll, Andrew(Science, 2008)Link to Published Version
Knoll, Andrew; Narbonne, Guy M.; Kaufman, Alan J.(Proceedings of the National Academy of Sciences of the United States of America, 1997)Link to Published Version