Play Challenge mode and reach the Seeded Pro level. Look at the leaderboard after each hole and look at your opponents' names. Some of the names listed are references to characters from Futurama, as follows.

"Fry" is a reference to Philip J. Fry.
"Leeland" is a reference to Leela.
"Zoe Berg" is a reference to Dr. Zoidberg.
"Conrad" is a reference to accountant Hermes Conrad.
"Ben B." and "Rodriguez" are references to Bender.