Mühlbachler, S., Langmayr, D., Lui, A. T. Y., Erkaev, N. V., Alexeev, I. V., Daly, P. W., et al. (2009). Cluster Observations Showing the Indication of the Formation of a Modified-Two-Stream Instability in the Geomagnetic Tail. Advances in Space Research, 43(10), 1588-1593. doi:10.1016/j.asr.2009.01.012.