Conversation so far:
what is the name of the right fielder in who's on first
The right fielder in Who's on First? is never identified. In the Selchow and Righter board game, the right fielder's name is Nobody.
who made who's on first famous
Who's on First? is a comedy routine made famous by Abbott and Costello.

Question: who is part of the duo
Self-contained rewrite: who is part of abbott and costello