Why did Hamlet request the actors to perform the play "The Murder of Gonzago"?

Until the staging of the play within the play, Hamlet has only the assertion made by his ghostly father as proof of Claudius's guilt. So when a troupe of actors come to Elsinore, Hamlet seizes the opportunity to test Claudius by arranging the performance of a play he calls "The Mousetrap." Hamlet asks the players to perform "The Murder of Gonzago," a reference to the murder committed by Luigi Gonzaga, who poured poison in the ear...

Until the staging of the play within the play, Hamlet has only the assertion made by his ghostly father as proof of Claudius's guilt. So when a troupe of actors come to Elsinore, Hamlet seizes the opportunity to test Claudius by arranging the performance of a play he calls "The Mousetrap." Hamlet asks the players to perform "The Murder of Gonzago," a reference to the murder committed by Luigi Gonzaga, who poured poison in the ear of Francesco Maria I Della Rovere, Duke of Urbino, in 1538. Because the ghost has told Hamlet that Claudius murdered Hamlet's father, who was asleep in his orchard, by pouring poison into his ear, Hamlet expects to get a reaction from Claudius when he watches the scene. Claudius does not disappoint, leaving the performance obviously flustered, and Hamlet secures the proof that seems to confirm what his father's ghost has told him.