Shotgun is listening to Ice Cube's 1991 release Death Certificate in the hallway where he's talking about Batman vs Spider-Man.
The verse that Shotgun is writing then recites for Inspecta is from Method Man's self-titled track off Enter the Wu-Tang (36 Chambers) (1993).
The beat Bobby plays for Dennis is All That I Got Is You from Ghostface Killah's first solo album Iron Man (1996)