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NICKNAMES OF PERSONS

Put a nickname within quotation marks or parentheses on its first appearance:
            Michael "Nick" Nichols
            Capt. E. J. "Scotty" Gall
or       Capt. E. J. (Scotty) Gall
            Walter J. (Wally) Hickel showed me his trophies.
            Wally told me ...

When the nickname is well-known, the given name need not appear at all, nor are quotation marks necessary:
            Babe Ruth
            Butch Cassidy
            Billy the Kid

See also TITLES OF PERSONS.