Gillessen, S., Eisenhauer, F., Quataert, E., Genzel, R., Paumard, T., Trippe, S., Ott, T., Abuter, R., Eckart, A., Lagage, P. O., Lehnert, M. D., Tacconi, L. J., & Martins, F. (2006). Variations in the spectral slope of Sgr A* during a NIR flare. Journal of Physics: Conference Series, 54, 411-419.