1. Tinoco, T., Polian, A., Gómez, D., et al., Progr. Surf. Sci. B, 1996, vol. 198, no. 1, p. 433.
2. Bovomratanaraks, T., Saengsuwan, V., Yoodee, K., et al., J. Phys.: Condens. Matter, 2010, vol. 22, p. 355801.
3. Gonzalez, J., Quintero, M., and Rincon, C., Phys. Rev. B, 1992, vol. 45, p. 7022.
4. Mori, Y., Iwamoto, S.-I., Takarabe, K.-I., et al., Progr. Surf. Sci. B, 1999, vol. 211, no. 1, p. 469.
5. Kumar, R.S., Sekar, A., Jaya, N.V., et al., J. Alloys Compounds, 2000, vol. 312, p. 4.