PHYSICA B, vol. 281, page. 731 - 733, 2000-06
PHYSICA B, vol. 281, page. 521 - 523, 2000-06
PHYSICAL REVIEW B, vol. 61, no. 13, page. 8936 - 8940, 2000-04-01
PHYSICAL REVIEW B, vol. 60, no. 8, page. 5348 - 5353, 1999-08-15
PHYSICAL REVIEW B, vol. 59, no. 15, page. 10018 - 10024, 1999-04-15