E. Ferreira, J. da Costa, J. Freire, V. Freire, and G. Farias. PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, 17 (1-4):
220-221(2003)International Conference on Superlattices Nano-Structures and
Nano-Devices (ICSNN-02), TOULOUSE, FRANCE, JUL 22-26, 2002.