Possible Clues:

• Cowardly Lion portrayer
• Cowardly Lion actor
• Bert who played the Cowardly Lion
• Bert of 'The Wizard of Oz'
• Actor Bert
• Cowardly Lion player
• Cowardly Lion portrayer Bert
• Lionized actor?
• Bert of "The Wizard of Oz"
• ''If I Only Had the Nerve'' singer