Buermann, W., Anderson, B., Tucker, C. J., Dickinson, R. E., Lucht, W., Potter, C. S., Myneni, R. B. (2003): Interannual covariability in Northern Hemisphere air temperatures and greenness associated with El Nino-Southern Oscillation and the Arctic Oscillation. - Journal of Geophysical Research, D 108, 4396.https://doi.org/10.1029/2002JD002630