Last millennium Northern Hemisphere summer temperatures from tree rings: Part I: the long term context

Rob Wilson, Kevin Anchukaitis, K. R. Briffa, Ulf Buntgen, E. Cook, R. D'Arrigo, Nicole Davi, J. Esper, D. Frank, Bjorn Gunnarson, Gabriele Hegerl, Samuli Helama, Stefan Klesse, P. J. Krusic, Hans W. Linderholm, Vladimir Myglan, T. J. Osborn, Milos Rydval, Lea Schneider, Andrew SchurerG. Wiles, Peng Zhang, E. Zorita