referenced in dialogue
mentioned by Sam
Balthazar talks about the Godfather
title is a song from this movie (which is also about breaking the fourth wall)
The angel buying weapons & shooting the shotgun in the gun shop
mentioned by homeless man
mentioned by Bob
Dean says, "Nice Blue Steel, Sam."
mentioned by Misha
Sam and Dean watch a clip from Days of Our Lives (1965) starring Jensen Ackles.
when Virgil is shooting everyone in the studio, one of the crew dodges the bullets Matrix style