May 9, 1980 to November 14, 1980
March 20, 1980 to March 3, 1981
February 29, 1980 to March 3, 1980
January 18, 1980 to May 18, 1980
December 16, 1979 to August 14, 1980
November 20, 1979 to March 5, 1981
November 9, 1979 to May 22, 1980
September 1, 1979 to March 14, 1982
June 15, 1979 to November 6, 1979
May 31, 1979 to June 17, 1980
