While patrolling the town border for immigrants, Peter brings Michael McDonald to provide back up for whatever he, Quagmire, Cleveland, and Joe say. This is referring to the often times McDonald has done backup singing for other singers or musical groups.
During the scene in which Peter and Brian are talking about immigrants, Peter says that "they are part of the Rebel Alliance and a traitor! Take 'em away!" This is a line said by Darth Vader in Star Wars Episode IV: A New Hope.
Upon the oral test of nationalization, Peter mistakes the phrase "Home of the brave" for the phrase "Home of the Whopper", which is the slogan for the Burger King restaurants.
When the INS interviewer asks Peter what is Lois' favorite outdoor activity, he answers multiple incorrect answers prompting the interviewer to give more clues. When a buzzer is heard, Dick Clark emerges he gives the perfect clue making Peter saying the right answer, which was Shower Cap. This is a reference to The $25,000 Pyramid, where players gave a list of clues for their partners in order to guess what all the clues have in common.
When Peter leaves a goat for Toby Keith, Lois says "Toby Keith doesn't want to be fed, he wants to hunt," a reference to Dr. Grant's line in Jurassic Park about the Tyrannosaurus Rex at the park.
When Peter comes back from his first day working for Mr. Pewterschmidt he calls Gerardo "Cheech" referring to Cheech Marin.
Speedy Gonzalez is parodied when Peter creates an American equivalent called Rapid Dave.