The writer of Yesterday Girl and Sidney Salkow are of the same nationality.
Alexander Kluge (born 14 February 1932) is a German author, philosopher, academic and film director. 
Sidney Salkow (June 16, 1911  October 18, 2000) was an American film director (more than 50 motion pictures), screenwriter, and television director. 
Yesterday Girl (German: Abschied von gestern, "Farewell to Yesterday") is a 1966 New German Cinema film directed and written by Alexander Kluge. 
