Julius J. Epstein, Philip G. Epstein and Howard Koch wrote the script that tops the WGA's list of the 101 greatest screenplays.
Among screenwriters still living, Woody Allen tied with Coppola for the most mentions with four apiece, the Los Angeles Times said.
Coppola's "Patton" and "Apocalypse Now" both appeared on the list while Allen's "Annie Hall" was No. 6. "Hannah and Her Sisters," "Crimes and Misdemeanors" and "Manhattan" all appeared further down in the list.
The other films appearing in the Top 10 included "Chinatown," "Citizen Kane," "All About Eve," "Sunset Boulevard," "Network" and "Some Like It Hot."
The Writers Guild has 9,500 members in the film and TV industries.
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