Nonlinear beam shaping by a cloud of cold Rb atomsG. Labeyrie, T. Ackemann, B. Klappauf, M. Pesch, G. L. Lippi and R. KaiserEur. Phys. J. D, 22 3 (2003) 473-483DOI: https://doi.org/10.1140/epjd/e2003-00046-4