Which American screen and stage actor, who appeared in "Casablanca" also appeared in the 1951 British-American adventure film "The African Queen"? 
The African Queen (film): The African Queen is a 1951 British-American adventure film adapted from the 1935 novel of the same name by C. S. Forester. The African Queen (film):  The film stars Humphrey Bogart (who won the Academy Award for Best Actor – his only Oscar), and Katharine Hepburn with Robert Morley, Peter Bull, Walter Gotell, Richard Marner and Theodore Bikel.
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