Bud asks a security guard whose name is Sue if his parents were Johnny Cash fans. This is a reference to Cash's song "A Boy Named Sue".
When Peter speaks on the phone with a fake Australian accent, it is in fact much closer to the real speaking voice of Australian actor Nic Bishop than the American accent that he uses for the character.
Ironically, Nic Bishop's "fake" Australian accent is criticized by Nathalie Kelley who also grew up in Australia.