The last two of six Russian ballet dancers to famously defect from the U.S.S.R. to the United States in the 1960's and 70's - Valentina Kozlova and Leonid Kozlov, who sought political asylum on September 16, 1979 - will commemorate the 30th anniversary of their celebrated defection with a one-night-only dance concert, 'The Legacy Gala' on Monday, November 23 at 7:30 p.m. at the Joyce Theater (175 Eighth Avenue) in New York City.