Annibaldi, S. V., Ivlev, A. V., Konopka, U., Ratynskaia, S., Thomas, H. M., Morfill, G. E., et al. (2007). Dust-acoustic dispersion relation in three-dimensional complex plasmas under microgravity. New Journal of Physics, 9(327), 1-9. doi:10.1088/1367-2630/9/9/327.