MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, vol. 82, no. 1-3, page. 108 - 110, 2001-05-22
JOURNAL OF APPLIED PHYSICS, vol. 91, no. 7, page. 4233 - 4237, 2002-04-01
INSTITUTE OF PHYSICS CONFERENCE SERIES, no. 169, page. 281 - 284, 2001-01