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<http://people.com/archive/david-letterman-could-succeed-johnny-carson-but-he-frets-that-the-last-laugh-would-be-on-him-vol-13-no-5/>
<http://people.com/archive/david-letterman-could-succeed-johnny-carson-but-he-frets-that-the-last-laugh-would-be-on-him-vol-13-no-5/>