%0 Journal Article %J Science %D 2007 %T A whiff of oxygen before the Great Oxidation Event? %A A.D. Anbar %A Y. Duan %A T.W. Lyons %A G.L. Arnold %A B. Kendall %A R.A. Creaser %A A.J. Kaufman %A G.W. Gordon %A C. Scott %A J. Garvin %A R. Buick %B Science %V 317 %P 1903-1906 %G eng