Phys Rev B Condens Matter
November 1989
Phys Rev B Condens Matter
October 1989
Phys Rev B Condens Matter
September 1989
Phys Rev B Condens Matter
August 1989
Phys Rev B Condens Matter
July 1989
Phys Rev B Condens Matter
July 1989
Phys Rev B Condens Matter
June 1989
Phys Rev B Condens Matter
April 1989