While visiting Frank in the psychiatry, Kai glances an eye at other inmates, seeing a guy playing Ludo against himself. This is the same guy Kai and Stefan almost kill in the first movie with the "brain-cell-massacre"
Stefan talks about sucking the dick of Memet Scholl. He says if he should ever suck a dick, it should be the dick of Scholl. This is a reference to the first scene in True Romance, where Clarence says, if he ever fucked a man, it should have been Elvis.
The first conversation in this movie is a copy from those in Pulp Fiction, wherein Vincent and Jules sit in the Diner and Jules is talking about telling Marsellus he's out of the gangster business. Then Vincent asks him when he decided that he's out while he was sitting there and ate his breakfast. In "Lammbock", Kai asks his buddy when he decided he only wants to talk about important problems of life while he was sitting there, rolling a joint. Also, movie poster is showin in background next to the "From Dusk Till Dawn" one.