APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, vol. 59, no. 4, page. 445 - 448, 1994-10
PHYSICAL REVIEW B, vol. 49, no. 4, page. 2651 - 2657, 1994-01-15
SURFACE SCIENCE, vol. 301, no. 1-3, page. 295 - 305, 1994-01-10