Farias, D., Kaminski, W., Lobo, J., Ortega, J., Hulpke, E., Perez, R., Flores, F., & Michel, E. G. (2003). Phonon softening, chaotic motion, and order-disorder transition in Sn/Ge(111). Physical Review Letters, 91(1):, pp. 016103-1-016103-4.