 David O. Selznick (qv), in a memo from October 1939, about the  movies writing credits: " [Y]ou can say frankly that of the  comparatively small amount of material in the picture which is not  from the book, most is my own personally, and the only original  lines of dialog which are not my own are a few from  Sidney Howard (I) (qv) and a few from Ben Hecht (qv) and a  couple more from John Van Druten (qv). Offhand I doubt that there  are ten original words of [Oliver] Garretts in the whole script. As  to construction, this is about eighty per cent my own, and the rest  divided between Jo Swerling (qv) and Sidney Howard (I) (qv),  with Hecht having contributed materially to the construction of one  sequence."